My sister and I have had a fractious relationship over the last few years. Her husband is a bit of a reform voting toxic masculine kind of man. We used to get on but over the years, have drifted apart and don't really have anything in common.
My son goes to our parents house after school one day a week and she tends to bring her own kids. As my son is getting towards high school, I've tended not to put him online. I don't have Facebook and stopped sharing him on Instagram about ten months ago when we had a conversation and he said he wasn't comfortable. All good.
My sister is a prolific sharer to the point I find it slightly uncomfortable. Think photos of her kids in high dependcy unit on oxygen and long narrative captions. She keeps putting photos of my son online so eventually I asked her to not do it anymore. I was very polite about it. She then blocked me on WhatsApp and Instagram.
I can't work out if this is a two fingers up like "you can't see my profile now so I can' do what I want" or a bit of an embarrassment / shame response. Either way, I don't know what to do now and I'm pretty annoyed that a normal parenting boundary has been responded to in this way. I could flag with my parents but I suspect they'd back her.