Genuine question - why do you honestly think MILs always say “my baby”

I truly don’t mean for this to sound petty - I’m honestly just curious if someone has given this some thought on a psychological level. I’ve seen many posts about new moms being put off by their MIL (specifically) referring to their child as “my baby” or some iteration of that. You can see my post history and see that my relationship with my MIL has been taxing since welcoming my son almost 6 months ago.

Is it perhaps the case that we’re bothered my MIL saying “my baby” simply because they’re our MIL? Or is it the case that MILs just feel the need to do it.

For example, my mom calls my son “my grand boy” or “my grandson” - she’s very specific about the “grand” relationship. My FIL will call him cute names like “little peach” or “little love” or something. My dad doesn’t gaf about him haha. I call him every cute name under the sun including “my baby”. My husband actually calls him “our baby” or “our son”.

My MIL quite literally incessantly calls him “my baby”. When she FaceTimes, the call literally starts like this: “my baby my baby my baby my love my angel my boy my baby my baby me little love my heart my soul my baby my sun” etc. We live abroad so usually my son is just like 😐 because he doesn’t know who she is.

Anyway - why do you think it is that ALLLLLL of her nicknames need to involve “my”? Is it innocuous and cute or is it literally some weird power play bullshit? When I was freshly postpartum, it caused me genuine distress because I was struggling to breastfeed and felt insecure about my bond with LO. Now, I feel great about our bond so the comments bother me less. But I do still find the comments very excessive considering they don’t even have a relationship.

Thoughts?