Explaining heavy topics to young children.

Hello mamas 👋🏻 so my oldest baby is 7 and her favorite show in the whole world is Supergirl (don’t worry, I watch with her.) She adores Supergirl & the actress who plays her. Anyways, earlier today the actress who plays her (Melissa Benoist) came forward as a survivor of domestic violence, she posted a video on YouTube explaining everything. The story was on our local news and my daughter gave me a puzzled look and asked me “mama? what does that mean?” I’ve never talked to her about domestic violence before and honestly I didn’t quite know what to tell her today. I didn’t want to make her upset, so I told her I’ll tell her later. My question is, how do you appropriately explain heavy subjects to young children? Or should you save the heavy stuff for when they’re a little older?