Mine too. Not to me, because I'm different from what she's used to, she's seen me kick off over another issue, and she's rightly a bit wary. But she was the school bully, has no friends as a result, bullies and emotionally blackmails her parents, bullies her siblings, though not DH anymore, and I suspect bullies her children.
It's all dressed up as "banter" and if anyone objects they are "sensitive" and it's "just a bit of fun" but it's bullying. It's like a default position to her. When my DC was at that slightly more interactive stage of babyhood, she visited one day and within minutes she was at it - holding things of of the baby's reach, blowing in baby's face, laughing when baby became distressed. I clocked on immediately what was going on and I shut that down so fucking fast she didn't know what was happening
It's the oddest thing, because in some ways she isn't bad, and there's possibly a normal person somewhere, but it's like she just doesn't know how to interact with people beyond making fun of them and trying to be domineering over them. She's recently moved back to her hometown to be near PIL and apparently is too anxious to go to the local park or shop or anything because so many people from school live in the area and they basically hate her