Is it scary to be a mother of 2?

Hello to all, can I ask a question, it might sound stupid to some of you, but I had to ask this; we (me and hubby) have been married for almost 8 years, happy marriage, we have a 6 year old boy, who has autism, life for my boy and us was really harsh, his difficulties, meltdowns, ups and downs has made us many times ask if we were doing the parenting right, we only have that one baby💙 but now we wanna try for one more, but we are really scared, how are the chances to be a parent of 2 if the first one is still very needy? How hard can it be? And also scared, I have had the first with autism, it has been so hard on him and us, that we still cry together sometimes… has someone esperienced this?