estranged code baby
Code that someone wrote that they no longer work on, but when they are around it they have strong feelings of ownership, love, or regret.
Him: I was doing a code review for a co-worker today and realized that he was working on the same code I wrote several months ago. I didn't really remember the code, but I felt something very familiar about it.
Me: It's a little estranged code baby!
Me: It's a little estranged code baby!