What is this?

Alicia

I discovered this under my baby’s armpit yesterday, and have a doctor’s appointment to have it checked out tomorrow.

However I’m wanting to see if anyone here has seen this...

UPDATE 11/16/18 - Anaiya went to see the doctor today, and this turns out to be a sore spot where moisture was allowed to remain too long. We will now towel off better after baths, wear cotton onesies underneath our fleece pj’s, and are putting diaper cream on this spot until it goes away.

Thank you for your comments!