"My religious grandma asked me, 'My religion is against trans people, what do you think should be done in raising a child that is not confirming to their sex assigned at birth?'"
What I think should be done is that you realize you're prioritizing a body of mythology and its prejudices over the well being of your child. You should realize that you're being a selfish piece of shit for doing that and that using this as an excuse to harm your child makes you a fucking monster.