Redeeming Xbox gift card on another account

My son plays games on the Xbox, so I have been collecting the Microsoft reward points get the Xbox gift cards for him. But I am using a different account to his. Can I use the points get the gift card for him to use on his account? I'm concern that when
I exchange the points for the gift card the credit will automatically appear in my account.

Can I give him the gift card (I'm assuming it's a code) for him to use? Hope I'm making sense.

:)