I would check out dogfoodanalysis.com and pick a new food for both dogs. You may find that both of them perk up a bit on a different food.
As for the pup wanting to eat the adult food....well, don't we always want what we can't have!? LOL!!
__________________  Rikki ~ Mommy to two amazing (human) children ~Lucy the great Dane ~  Piper the Maltese/Yorkie mix 3/19/10-6/28/11 gone too soon  |