You cannot have more than one passenger on any one ticket; each passenger has his or her own ticket. It is possible to have multiple passengers on a single PNR (reservation record). Is that what you are hoping to accomplish, and if so, why?

Keep in mind that AAdvantage awards are offered as one-ways. A roundtrip itinerary is simply the combination of two one-way awards. Any AAdvantage member can redeem miles for awards for family members or anyone else, as long as nothing of value is received in exchange for the award tickets.

There is usually greater flexibility in booking a roundtrip itinerary as two separate one-way awards. Occasionally, but not very often, AAdvantage award travel booked as a roundtrip will cost somewhat fewer AAdvantage miles than the sum of two one-ways.