My son is 5 years old and a cpl months ago he developed a huge knot on the left side of his head I figured he bumped it playing on the playground and I didn t worry about it until 3 weeks later I notices it was still massive and still there so I called a triage nurse and she said bring him this n this n she said if it goes away don t worry about it. Well the next day it disappeared like completely gone so I didn t worry about it. Well here we are a cpl months later and last night I noticed that spot looked red I asked him of he d hit his head etc and he replied no to all questions of and bout injury so I waited figuring it would go away maybe he scratched it. Well I noticed today at about 330 when he got home from school that he had that massive knot that just appeared over night and when I say massive I mean massive. He says it hurts but doesn t complain doesn t itch no fever no injuries nothing so I m scared and worried and desperate for answers. I called his Dr and they have absolutely no clue what it could be so maybe you do