Busted Lip?

Kat

My mil watched my son Saturday and when we dropped him off I noticed she had some kind of sore on her lip so we stressed no kissing him. She acted insulted that we had to mention it. The next morning we noticed he had a spot on his lip and thought it might just be where he bit himself. This morning it's way worse looking and he also has a smaller one on the inside of his upper lip. Does it look like he just bit it or something else?