This thing just suddenly appeared.. What is it?

There's no way to really tell how your baby got it, but all I know is that it is super contagious and needs to be treated ASAP! It's not life-threatening or anything as far as I know, so don't freak out! But like everything that was said above, you gotta be diligent.

Are you breast feeding or bottle feeding. If you're breast feeding you can get it too

You have to call the dr to get an antibiotic or it will get worse. My niece just had it. And hers got pretty bad. Make sure you're cleaning bottles very good and boiling them to sanitize them. Especially after you get the antibiotics or it will just get worse and come back.

@katiesolger, @mamalamadingdong how did that happen? If I always checked my baby... How can I treat it?

I agree^^ thrush

Can it wipe off with a warm washcloth if not then it looks like thrush

the white patch on the lip? kinda looks like thrush or could be a glare lol