Weak chick, what is the lump?

[froghollowfarm2]

One of my chicks, four days old, is not doing well. I don't think she is pasting up, but below the poop hole there is a black, hard lump about a quarter inch diameter. I have been wiping with both warm water and baby oil, but it almost seems to be a growth. It's a Buff Orpington, and she is smalled than the other ones and she seems a little weaker.
I'd appreciate any suggestions and help. Thank you.

 

[RendonRoo]

Not sure about lump. If it's weak you can give it some smashed up boiled egg. It will help give it a boost. Hope someone else can chime in here. Mainly trying to give you a bump on your thread. Good Luck

 

[SurprisingWoman]

I have never seen pasty butt so I can't advise you but I can give you a bump.

Sorry, I hope it's okay.