Recently my mom signed up for the frequent flier program at United and she used the same FF
# for herself and for my dad when they flew on vacation a couple of weeks ago, but it seems like she only got credit for herself. For example she ended up with about 3,200 miles for a roundtrip flight from ORD
. So I ask should she have gotten more miles, or is there some rule the airlines have against using the same FF
# for multiple passengers on the flight?