A bottle liner or insert for administering at least two different liquids to a feeding child, includes a first reservoir of polymer fabric, the reservoir comprising two walls sealed together at their mutual bottom and sides and having an open top and flaps extending from both walls at the top of said first reservoir a sheet of polymer fabric having a smaller area than either wall of said first reservoir, the sheet sealingly anchored to the inside of either wall such that the sheet and inner wall together form a second reservoir extending to and open at its top, the sheet also having a flap extending from its wall at the top and a valve in fluid communication with and disposed between the first and second reservoirs.