Did I do something wrong?

So I went pumpkin picking with my sister in law this weekend. My kids are older, she has a one year old and a 2 year old.

Her one year old pooped, so we went to her car to change her. I decided to come to help. My sister in law wiped her, and i simply asked “did you get it all?” I have a daughter so I know it gets everywhere. She was like yes, I got it all. So just to make sure (I don’t want my niece getting a uti) I checked to make sure she was totally clean, and wiped one more time.

My sister in law got a little weird after it.

I texted my brother to ask what my sister in laws problem was, why she got so cold towards me, and he told me that she doesn’t like how everytime she changes her kids diapers I come “breathing down her neck” to make sure she does it correctly

I don’t think I did anything wrong. I am just trying to help, and I am an experienced mom, and she is not

I think she’s being dramatic