Father visitation

My sisters Sperm donor wants both kids every weekend I think once a week! They aren’t together they’re is no court order in play we’ve been to court it got dismissed cause he filed for divorce they are trying to handle it on there own my sister is alllwing him to see the kids but her daughter my niece does not wanna go she’s screaming and crying bloody murder that she does not wanna go with ! He picks her up and throws her in ur car and proceeds to yell at her ! Since there’s no court order do we HAVE to let her go or can we keep her away until we get a court order visitation in order !? There is no abuse going on she just doesn’t wanna go and we feel so bad ‘ but we know she has to go! We are going to look up legal aide for a lawyer asap but in the mean time DO we HAVE to let her go !?