What is this rash??? 🤔

Carla

So he's had this off and on above his butt and this area is never in contact of urine or feces. I'm currently trying colloidal lotion to see if that might help but what is causing this? Anyone's littles experience something like this?

We asked his doctor about it a few days ago but he didn't seem concerned at all.

He gets lots of diaper free time too, so I don't understand why he has this.