Edzz,
Well this sounds like something that needs to get straightened out quick. I'd start by going into your Contacts app, deleting whatever Mom/Dad stuff is in there now, and creating new contacts for both of them. Take extra care entering phone numbers and email addresses, since this might be the source of the confusion.
Then it wouldn't hurt to start a new thread with each of them, separately — just text them anything to get it going — and leave the threads open.
Good luck!