I'm thinking of taking an unvaccinated child to a friends birthday when she asked for no unvaccinated people
That doesn't seem very kind of you. Do you have to?
Yes, I hope she doesn't find out.
There might be a reason for people to not have people who could be contagious at a party. You should respect their wishes or never reveal the truth and have fun.
She complains about child vaccinations so I hope she doesn't find out.
I think you should just stay home instead of potentially infecting a lot of people. You don't know if there are immunocompromised people there, so wouldn't it make more sense to try and keep them safe instead of hurt? You can always opt in for a video call to not miss out!