SIL constantly criticizing my toddler

My son is 15 months old, there is nothing medically wrong with him, he meets all his milestones and is a very happy, silly toddler. I don’t see my SIL often even luckily however, when she does see him there’s always something “wrong” with him.

Some examples what she has pointed out that have been “wrong”:

•He had a scratch on his face when he was a newborn from his nails, in front of everyone she had to physically point at it and say “what is this”

•She says something is wrong with his speech, he should be talking more and not babbling as much, (again he has met his milestones, ped not worried)

•the biggest one, she asked me if my son had hip dysplasia out of no where because she felt he was walking funny and his hips don’t align (he doesn’t)

None of this comes from a place of concern. It’s to make her feel superior or bring us down. I regrettably shared I was going through ppa shortly after giving birth and I feel like she uses this to hurt me.

I bite my tongue and have for years previously over other things because everyone in the family says “that’s just how she is”. She’s rude, inconsiderate and thinks she knows best despite her own children having extreme behavioral issues.

My question, next time she says something do I continue to bite my tongue or confront her? We have an okay relationship, I generally don’t speak to her at gatherings or share any personally information. If I say something, she might like the rise it gets from me and continue to push buttons even more. However I don’t want my daughter growing up hearing things that are “wrong” with her or other kids.

Lastly, my husband agrees with me. She’s caused problems in the family previously and he doesn’t understand why she is the way she is. He is very passive and generally things fall right off his back if he doesn’t agree. Him confronting her circles back to her knowing I’m upset, and possibly continuing to push buttons.

She’s been like this all her life according to my husband, just nothing but causes issues.

TLDR; SIL says things are wrong with my toddler every time she sees him, I haven’t confronted her, and doing so might make it worse or the family dynamic weird.