I am in the same situation with a 12 year old step daughter.
We're just trying to make sure she knows nothing will change.
It's the comments (that I ignore), but they silently upset me when I just want to be happy about our healthy baby considering we sadly lost the last one at 5 months along which she knew left me distraught.
before we knew gender it was "I don't want it to be a girl, I'm the only daddy's girl." And I mean she would say this 1000 times!
Now we know it's a girl, (I already have 2 girls), I'm thrilled because I love girls.
This time, I just want to be happy that it's healthy and just enjoy it but I have a very sad 12 year old step daughter.
My two daughters are excited, but step daughter was openly not happy about it being a girl and won't stop saying how "it could be a boy, they may have got it wrong". Constantly......
I just want to enjoy it without the comments 😫
This is the only time I have ever expressed how I feel and of course would not show it in front of step daughter. Just wish she would come around. Maybe she will when the baby is born.