Belly button help! So Mariella's cord stump fell off (finally!) and now like the top and bottom of…

Belly button help!

So Mariella's cord stump fell off (finally!) and now like the top and bottom of her belly button are stuck together with some gunky brown stuff, it's like hard and crumbly looking. Should I take a warm wash cloth to it and try to get it off? I don't want it to get infected underneath and not notice it, ya know. Any input would be helpful! Also, if someone could explain what they are supposed to look like the first couple days after, that would be extremely helpful! Thank you!!!!!