Originally Posted by
blueskeyes
It's very easy. I'm a plat, and I've done this for my parents, and for my in laws.
When I've done this MR usually puts a note in the record and they often get upgraded to a nicer room, as well receiving as the platinum amenity.
I gave an award stay for my sister last fall. She got the upgrade, got lounge access but did _not_ get the platinum amenity. However, _I_ got the points for the incidental room charges.
The bottom line for the OP is: You have to call Marriott Rewards to book this and order a certificate. It cannot be done online.