Fly Together Act This bill requires the Department of Transportation (DOT) to establish a policy on seating a young child (i.e., under the age of 14) next to an accompanying adult on a flight. Specifically, DOT must direct air carriers that assign seats or allow individuals to select seats in advance of the date of departure to seat a young child next to an accompanying adult, to the greatest extent practicable, if adjacent seat assignments are available. An air carrier must do this without charging a fee or an additional cost beyond the ticket price of the additional seat.