I think she is totally clueles..
You might have to treat her like a 12 year old.
Tell her,,, my child is 5. He can only play with toys for preschoolers at my home. We have other things to do at home besides video games.
Does she even know your XWH is behind in child support?
Seriously, I think she is a "slow" person. You might really have to teach her some things that she needs to know since she will be parenting Teslet.