Age of children for context is important.
I wouldn’t allow the friendship with your daughter and this friend to continue. Don’t allow her in your home. Let your daughter know that her friend lying like this is not a good quality in a friendship. It will get worse from here. Speaking from experience, both as in my childhood friendships as well as watching it happen with my kids.
Do not take any chances. Keep her away from your home and son. This sounds like a huge problem waiting to happen.
Keep her out let her know your on to her
Follow her instead of leading her then she can’t lie about anything
I’d tell her no because she keeps lying and saying your son hurt her.
Unfortunately I would have to end that relationship and explain to both kids why. She would not be allowed in my home or around either of my children - lying can be dangerous and hurtful and I wouldn’t allow either of them to be around a behavior like that they could pickup on or end up hurting them.
Don’t let her in your house easy peasy.
I would inform her and her mother that since she has chosen to lie again and again in regards to your son causing her pain or injury even in front of witnesses who knew she was lying that she is no longer welcome in your home
Is this a serious question?! You know the answer! Like damn ! Do not let this child in your house. You asking for trouble
I would have a chat with her parents!! If you can’t then end this friendship! Sounds like trouble.
My kids wouldn’t play with her at all.
I would keep her away from my kids just like you said before she makes up a terrible lie that can effect the whole family. She is not a friend and obviously is a pathological liar which is serious. You didn’t say whether or not her mom backed her on her lies or not of if she was punished for telling lies but in any case I wouldn’t let her come over any more. Tell the mother why so maybe she can take her daughter to a professional before her lying get totally out of control. She has issues that need to be addressed. 
Do not let her go into your house
I think knowing all of their ages would be helpful…. But I def would cut all contact. Don’t let her back into your home.
Dont let that bebe kid in your house! If the roles were reversed, everyone would be saying he is being pushy and not respecting her boundries. Same goes for her.
If this child is young/pre teen, I would be concerned that there is something going on at home or in her life. It seems like she is attention-seeking and that is often a cry for help or a need to be seen/heard. 
Try to have a conversation with her before shunning her. She made need that loving energy.
You don’t let her go to your house, Jesus lady. Put YOUR kid first, how do you think this will be affecting him
Your the parent,record her and video the proof in case the parents take the child that’s telling lies side.Take control now because the older the kids get,the bigger the problems…
Also can we stop teaching our kids that when another child is mean to them it means they have a crush.
Just set her down and tell her lf she keeps lieing than she can’t come over and play
Don’t take that responsibility
Not let your kids play with her. Sounds like she would be a bad influence.
You have to protect your son above all
Don’t let her in. Your son comes first.
End that relationship, because you’re right, it could get worse. I would protect my kids before she said something worse
To me it seems like she’s crying out for some kind of help!
set up a video camera or baby monitor. My niece used to lie a lot so I would leave the baby monitor in the room where they played so I can hear what was really going on.
If it were me and my children I’d keep that kid away from my kiddos.
If she is in your house never leave he alone but it’s safer to not let her in at all
Ummm tell her no! Its ur house hello
No maam protect your son
DONT DO IT
DONT DO IT
DONT DO IT
if she lying about what’s going on outside what will she lie about what’s going on inside
DONT set yourself or your son up
I would tell both your son and daughter to stay as far away from as possible if her own brother is telling his parable she lying and nothing is being done I can only imagine that this is going to get worse
Set boundaries. I wouldn’t allow inside play time with her.
I hate to say it. But unless you and her mother have a talk about what’s going on with her then I wouldn’t allow her over or for my kids to play with her. I know that sounds horrible but I’ve got to look after MINE first. Especially if they’re not doing anything.
Umm seems simple, don’t let the kid come around. Tell mom why.
Don’t do that to your son… leave her in her mama house
Yup, that girl is trouble. You keep her away from your house.
Tell her to knock it off, real simple
Talk to her mom in person, also if she’s gonna come over I would either have the kids in the living room or a room you can watch, or put a baby monitor/camera in the room they will be playing in…
For doing work in spare time i maklng $ 500 every day using my mobile. l never th0ught l c0uld d0 that, but my frlend w0uld earn m0re than $ 17,270 a m0nth and persuade me t0 glve lt a try. The p0sslbllltles are endless.
Can you not talk to her mum? So she can start teaching her daughter that lying isn’t good? It will never get sorted if her mum/dad doesn’t even know what’s happening… but yes I agree, that’d your child’s home & safe space, I wouldn’t allow her in until its sorted and the lying stops…
I wouldn’t let her over or play with my kids. She’s trouble!
Simple solution. Do not allow her around your kids. Not only is that putting whoever at risk of false accusations but you dont want your kids to pick up that behavior as well.
Go by your gut feeling they are always warning you
I wouldn’t allow her to be around your kids if I were you. Hopefully she will learn the lesson of consequences but ultimately I wouldn’t want your son or daughter accused of something they didn’t do. Especially if she was inside your home. Don’t risk it.
Don’t let her play with your kid. Bad habits spread easily between children
Are they 5, or 8, or 12 or older?
I would stop having her over or taking her places. I’d tell her and her mother why.
This is heading for no where good!
I’d have a chat with the friend. Ask her why she lies, why someone has to be at fault when she hurts herself. What happens at home when she hurts herself? If her parents are divorced, does her mom make her say her dad caused all her bruises and scrapes? Is anyone physically abusing her and telling her to lie about where she got her injuries? Is she not getting enough attention?
Talk to her mom to see what’s going on. Explain that until she gets help for her daughter’s lying and the underlying issues she can’t come over and play with your kids. If she comes by, have your kids come in the house or take them to a park away from her.
You’re in no way obligated to let any child that doesn’t live with you in your home. Period.
Send your son to a friends for day. If the girls are inside, let him play outside or vice versa. She sounds like a little brat and you’re right, it’ll probably get worse if she comes over.
FYI:
“Compulsive lying is usually thought to develop in early childhood, due to being placed in an environment where lying was necessary and routine. A lot of them find it easy to avoid confrontations with truth, hence they stick to lying. Compulsive liars may or may not experience a mental disorder.”
“Pathological lying is a symptom of various personality disorders, including antisocial, narcissistic, and histrionic personality disorders. Other conditions, such as borderline personality disorder, may also lead to frequent lies, but the lies themselves are not considered pathological.”
“An important part of diagnosing a pathological liar is determining if they recognize that they’re lying or believe the lies they tell. Some professionals use a polygraph, also known as a lie detector test”
“Can Compulsive or Pathological Liars Change? In Ekman’s experience, most liars who are compulsive or pathological don’t want to change enough to enter treatment. Usually they only do so when directed by court order, after they’ve gotten into trouble, he says.”
Don’t let her in. If a child lies and is disrespectful, tell her the reason and send her home.
Do not ALLOW her to come over…I’d speak to her mother also as to why she can’t come over.
Don’t let her play with your kid
I wouldn’t allow her over.
Protect your son period!
Cut ties and move on lies will only get bigger
NOPE. Next thing you know she’ll be accusing you or your husband of “touching” her. This isn’t likely to change - something is already “wrong” and her parent likely doesn’t see it, and would refuse to get help for their unbroken princess.
I would not let her come over. I couldn’t subject my son to that. Just say she can come over next time. Be kind. Say you have too many kids over. Etc.
Keep her out
Don’t let her near the house
Don’t let her come in… tell her why or her Mom.
Don’t let her in and say why would you want to come over if you say my son is always hurting you then you wouldn’t want to be around us 
Protect your son! That is a definite no.
Don’t let someone who is rude to your kid in your house, that’s their safe place why would you invite anxiety for your son into your house? They can play outside but your son deserves the right to not be bullied in his own home because yes that’s bullying in my opinion
I wouldn’t be letting her come over
don’t let her in your house… send her home if she comes to your house… her mom already knows what is going on and will blame you even if she already knows what an evil child she has birthed… one kind word from you will be your down fall… sorry for your situation…
Nope. Nope. Nope. Bad idea. Absolutely nothing good can from her being in your house. I’d keep all your kids away from her.
I wouldn’t let her near my family at all. Liars aren’t welcome here. My biggest peave. We all aren’t perfect… not being perfect is ok… lying is absolutely not… yes there is some learning around this required… but if she has been caught, talked to and continues… NOPE. gtfo
Tell the mother. Straight up tell her. If there is some conflict over it, oh well, see ya, not welcome at my house. Tell her everything.
bar her from playing with your children.
Don’t let her in your house!
Keep her out she’s a liability 
, she’s toxic
Keep her away from him. That’s scary.
Protect your son and keep that girl away from him!!!
Nope dont allow it till she corrects her behavior.
She WILL make up worse lies. Protect your son and DO NOT allow that little girl near him. I can’t stress this you enough.
Absolutely not. I wouldn’t let my kids around her period.
How old is this girl? That would determine my response. If she is old enough to know better I’d tell her outright that I’m sorry she can’t come over because I’m tired of her lying about my son hurting her and then shut the door. If you restrict her without feedback of what she is doing wrong she will not have a chance to correct it, learn and grow from it.
Do not let her in your house.
Don’t let her in your house protect your son
She sounds like she has some problems, don’t make those problems yours let alone your poor son!
Toxic behavior. She should not be allowed to come to your house. If her mother hasn’t dealt with the lying, she could possibly put y’all in a difficult position. I wouldn’t let her near my kids without watching constantly.
Keep her out. Personally, I would use appropriate words to tell her why. Although, I know you don’t owe that child an explanation.
Not all in the house
Tell her mother she has a lying little # for a daughter and if she continues doing what she’s doing. You will kick it’s a.s for it and bar it from your house or anywhere near your kids. I will also go as far as to tell the sch the same thing. NEVER ALLOW IT TO ENTER YOUR HOUSE NOR YOUR PROPERTY FROM NOW ON…
For doing work in spare time i maklng $ 500 every day using my mobile. l never th0ught l c0uld d0 that, but my frlend w0uld earn m0re than $ 11,978 a m0nth and persuade me t0 glve lt a try. The p0sslbllltles are endless.
Explain to her first if she continues to lie then she won’t be allowed back and it start right there and then. If you’ve already explained then don’t let her back
No…and if asked, be truthful…you are not comfortable having her around your son because of her actions
Since you talk about her maybe having a crush on your son im assuming she is old enough to know right from wrong.
Personally id be asking her why she feels she has to tell lies …since you have proof that she is…and telling her she’s no longer welcome to visit unless she can be honest
Id also call her mum and tell her why this is being done. Explain you cant have her accusing your son of violence towards her
Personally i would not allow her to come over at all
Let your daughter go visit her friend. Do not let her in your house especially if your son is at home.
To stay home or stop
Lying,
Call her parents, tell them she cant come anymore. Pathelogical lying can be a serious disorder they need to know
Honestly I would sit down and have a heart to heart with her. I’d be completely honest and upfront with her. Make it clear you won’t tolerate lies and provide her of an example where she has lied. Maybe even discuss your feelings about her having a crush on your son and how that situation is going nowhere. Tell her you will give her one chance to be a civilized individual and come in and play but that’s the only chance she will get. Let her know that at any time she decides to lie she will no longer be allowed over period, inside or out. Some kids need that confrontation. Remember she is a child and there may be other underlying issues on why she feels she needs to make things up. Maybe she needs a little adult guidance that may be lacking at home. Mind you I would also be keeping a very close eye on her while she is playing.
I would stop letting them play and she definitely would not be coming in my house. It will only get worse!
I had a friend like that growing up and her lies just got worse and disturbing! She would lie about stuff that could destroy families and or put people in prison! It was SO BAD!
I would be afraid of what she might accuse some one of once she went home of, when she left. Even a confrontation with her telling lie’s. She could say you slapped her. Always have a witness when she’s around.
Don’t let her. Period. You owe no explanation and if you feel like you do then tell the truth.
How old are these kids? Have you spoke with her parents?