I really need some advice to calm me down mentally

I’m 25 weeks and enjoying my pregnancy. Baby kicks everyday, everything is going well.

The issue I’m having is when my sisters come over. One of them miscarried a couple of weeks ago and she talks about it often. I kind of stay quiet because I hate hearing about it, talking about it. It seriously scares me sooooo much.

My mum had a stillbirth in the 90s and I always think it’s going to happen to me. How can I have these conversations without completely shutting off? I want to stay positive but it’s hard to when you’re constantly overthinking and comparing other peoples situations to yours..