SIL????

I'm a FTM and was recently blessed with our son.

We absolutely adore him and it melts my heart to see how much SO's family adore him too.

I have always been concerned with my SIL though. She is a lovely woman and we have had no issues in the past. She is very strongly opinionated especially when it comes to children. She doesn't have any children of her own and isn't expecting either. She has babysat children before and is of the opinion that she has a wealth of knowledge in raising children.

What has recently frustrated me is that she seems very possessive of my son. Initially I would shrug it off as I thought she was just a proud Aunty. Now it's turned a bit strange. If I visit their house (lives with FIL and MIL) she will hold him for as long as possible. If I wasn't breastfeeding she would hold him the whole visit. As soon as he comes off the boob she will rush to grab him again. She also calls him her baby and tells me to get my own. At first it was a joke but now she says it all the time and it has gone past funny. If I go to give him to my MIL she will take him off her asap. More recently we went shopping together and she took him out of the pram when I wasn't looking and walked around away from me and i overheard someone make a comment assuming he was her son and she didn't correct them and made out he was her son. This made me uncomfortable and to be honest jealous and our trip ended shortly after that.

A few days later we went visiting and my little man was asleep on a rug outside in the sunshine. My FIL told me I should take him inside because he was going to cut the grass my SIL had just arrived and walked outside and was like "I'll grab him." Hadn't said hello to me or anything. I wanted him to have some floor time and I knew she wouldn't understand that so I just picked him up and walked inside. A few days later I felt bad but I decided nope, I need to stand my ground with this.

Anyone else in the same position.