Numb3rs Fanfic Finders

Hi,

I'm looking for a series. The first story is a Charlie story only mentioning Don who was kidnapped as a kid and so he is "a perfect son" forever.

The second one is a story where Charlie gets help from Don (the FBI agent) for looking for his brother Don. In the end he learns that they are the same person. Don was kidnapped when walking home from practice (they forget him because of Charlie's lesson I think). The kidnapper was a pedofile.

I think it was on ff.net, but I don't remember the author or the title.

please help,
thanks