Thank you for placing your query with Health Care magic
What you describe can be a range of things
1. Lipoma: its a a very localised overgrowth of fat. It can occur anywhere on the body
2. Sebacous cyst: It a cyst with collected sebaceous material within the skin.
There are a few other soft tissue
swellings too that can happen in this region.
The only treatment is removal of these swellings surgically but they are slow growing and you can wait for a while.
3. It can be the beginning of an abscess
(collection of pus) although unlikely as you said it is not painful or red. But still you should get yourself examined by a pediatric surgeon to get a proper diagnosis. If it is an abscess then you will require to take antibiotics and analgesics ( and drainage
of the pus)
Hope that helps
God bless you