Dear Mr Wilson
Most falls in childhood do heal well by themselves and that is most likely what has happened in the case of your son. However, the lump you see at the same spot may be a healing at the site of a small fracture
. This is usually nothing to worry about and it will even out in the future. However, it is prudent to consult a doctor so that he can confirm that this is indeed healing bone (callus
). There is a small possibility that this may be a dermoid cyst
or inclusion dermoid, both swellings common in children on the head and it may be that the fall has only made it obvious to you since you are concerned about the region. For both reasons, it is worthwhile paying a visit to your local doctor. Please keep me posted if you have any further queries.