My 5 yr old daughter has a small light gray bruise near her shoulder with a bb sized lump underneath. she doesn't remember bumping it. what could itbe?

Need further testing: It could be a benign mass, could be cancer. Could be resolving trauma, even without recollection of trauma. First visit should be to pediatrician, if needed surgical follow up or imaging study such as cat scan or MRI can be arranged.

Bruise: Without seeing at least a picture of the bruise, it is impossible to renderan opinion asto what the problem is.