SOLVED. Hero and Heroine grow up together (mafia/gang). [s]

[Kris]

Want You by Jen Frederick seems to match your description.

"How old are you?" ... "Five, huh?" ... "Got a name?" ... "Noosance," she repeats. ... "My name is Leka, but everyone calls me Monkey."

(Google search -- site:www.goodreads.com "contemporary romance" gang "he raised her")

[Kris]

Great. Glad you found your book, Ashley.