Sister in Law Acts Like Our Baby is Hers on IG

Ok ladies, I need your help. My sister in law is single with no children. Our baby is 16 months now and she has treated me horribly since the beginning, always acting like she wants me to go away and take my baby, and has even talked badly about me behind my back.

I have spoken with her and we “resolved” things but nothing has changed so I have simply limited my contact with her. She has been to our house maybe 3 times in 16 months. She lives right down the street. We have welcomed her many times but she makes no effort to have a relationship with me or my baby, but then acts like I keep the baby from her.

Anyways, the problem I need help with is that she posts videos of photos of my baby on her story constantly. She even has two sections of highlights devoted just to my baby. These are not even her photos! She screen shots things from our posts or stories and uses them! She is never actually there in any of the photos or videos.

We do see her a couple times a month for family gatherings, holidays or what not so I feel like I can’t just say “stop doing that”. Any advice on how to approach this and explain it to someone who clearly doesn’t realize this is crossing a boundary?