I asked a similar question back in post #395. I e-mailed MyPoints customer service to ask. The answer was No. United will look for the name on the MyPoints and MilagePlus account to match. I also know for a fact that if you already have your MP number associated with your MyPoints account, if your family member attempts to put your number in on their account when redeeming for the reward, they will get an error message that the MP number is already associated with another members MyPoints account.