Don't know if there's a particular order but you could always test it to find out. Pinpointing one child window in particular would require at least one other unique piece of information about that child. For example, if you know the id you could retrieve it with
CWnd::GetDlgCtrlID (or
::GetDlgCtrlID) based on the child window handle sent to your EnumChildProc and look for a match.
The questions and answers you're asking and receiving in this thread seem very similar to what you asked and the answers you got
here. Given that similarity, I think you should try some of this out and see whether the information meets your needs.