Is your sister an obnoxious person in general? Pregnancy is the time to distance yourself from obnoxious and toxic people. Or at least put them on an information diet.
My mom is great but my aunts (her sisters) are super obnoxious. Not malicious, but completely lacking in grace. I've talked to them only once during my pregnancy and shared very minimal details. They were still somehow super obnoxious, even without info, and I was emotionally upset after my phone call with them. Like they know exactly how to upset you. My mom was pissed and straight up told me to avoid her 'crazy sisters', to love them from a distance.
You can love your sister but you don't have to listen to her bullshit commentary about your pregnancy.