As the previous poster stated she can take the free bus to terminal 4/Barry Goldwater.

If she has no bags or not many.,,,Meet her at the Pardise Bakery in the middle of terminal 4 on the gate departures level,,, not ticket departure level which is below. Paradise Bakery is easy to find and she will not have to go through security. You both can go downstairs to get your luggage if you have any and rent your car