I agree w/ pp ... if it doesn't go away, it's probably thrush. It will probably also get progressively worse over time (more and more white). You can also lift up the lips to see if it's on the inside of the gums and lips, and it might also be on the sides of each cheek (white spots). It is a truly maddening problem.
Re: For those LO with Thrush...
If it's thrush, you won't be able to scrap off the white stuff in your LO's mouth. It might look cottage cheesy, too.
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