I hate being forced to search for the first book in a series... So this should help and here's the full summary

www. fanfiction s/13453397/1/To-Understand-You

Link is spread out because fanfiction hates the full link? weird

It's been approximately 4 years since Kaito was adopted into the Nakamori Household. 4 years of healing, therapy, surgeries, and adapting. Kaito has recovered quite a bit, he still can't feel his legs though, but that's okay!

His life is so much better than it'd been when he could walk anyways, having a real family is nice...

Wait... Why did the hot detective that Kaito had a celebrity crush on disappear and get replaced by a tiny child in the newspaper?... Hmm This may need some investigating, and possibly some kidnapping.