I agree with forshelby - there is something else going on.

She is lashing out because she is upset or hurt about something and maybe she doesn't want to talk to you about it so just says she is ok ITMS?? Does she have another trusted adult friend that can sit and play with her and try to get her to open up about her real feelings?

I wonder if something has been said to her at her daddy's house about another baby and them being a new family ... or something along those lines. She may "get it" but perhaps she is feeling like she won't be wanted there anymore or that she is not part of "that" family, sort of an "out with the old, in with the new" type feeling??

Maybe she sees their little unit and is worried about you and your DF having a baby or something??

I dunno hun these are just things off the top of my head I am by no means an expert nor have I been in this situation.

I DO believe there is something that has upset her and that its playing on her mind causing her to act out. I also believe that she will not tell you without some serious prompting. Maybe she has been told or she might feel like you or her daddy won't love her as much if she tells??

Massive hugs hun, I hope you get to the bottom of it.

Nae x