Basically, Marriott will allow anyone to transfer points to someone's account as long as they are ordering an award. The T&Cs does state that this is only for spouses, but in practice they will allow any two accounts.

BTW, I recently pulled points from my mother's account for a series of awards. No questions, no problems. Just give MR a call, tell them you want to pull points from another account. They will fax you their form. You have to fill it out, sign it, get the owner of the other account to sign it, and then fax it back to Marriott. Actually, its not too hard.