In Law drama

So I just found out I’m pregnant with baby number 3, 13 months after having baby number 2 🥴 honestly was not quite ready but I’m over the moon about it. I told my mom who I knew would be super supportive and happy. Buuut the hubby and I do not know when we want to tell his parents.

Let me give a little backstory. So his mom lives with us because her and his dad got into a physical dispute and she went to jail. She was on drugs and became delusional thinking everyone was plotting against her and a bunch of crazy stuff. Flash forward to now, 2 years later she is STILL living with us. When my second daughter came she constantly told us what we should and shouldn’t do with her and she would offer to watch her and then later on rub it in our faces that we had to ask her to watch her. So I set a rule that if she was going to act like that then she wouldn’t be allowed to watch her. It’s been so bad that we have barely been able to sleep train. I don’t do the cry it out thing but with my first daughter we would let her cry a few minutes, come and comfort her, rinse and repeat until she fell asleep and eventually she started sleeping alone. With my second, we will be in the first minute or two of crying and my mother in law goes in the room and will pick her up. We constantly tell her she cannot do that because there is a method to the madness but she is constantly overstepping her boundaries…

so anyway, she is constantly saying how she doesn’t want anymore grandkids and telling us we “better not” get pregnant and so on(her and my father in law both say this). They both also know good and well that we have planned to have more so I think it’s pretty messed up.. Well lo and behold here I am with a bun baking and we have no idea how to tell them. I don’t want to tell them at all because I don’t want to deal with their negative attitude. We already have enough stress because this was not the best time for number 3, but as parents, we will always make things work for our babies.

What do you guys think? How should I go about this? His mom still lives with us so I can’t hide it forever