dogs can be fussy if you allow them to be. i don't have a clue as to why yours won't eat lauren, and im not that clued up with kibble food, so don't know what arden grange is like, but for both of them to have stopped eating it, maybe you should look around for something else, lol, they are obviously ganging up on you . its true that dogs don't really need grains and i think there are some varietys on the market that don't have any, but i feed raw so my knowledge is limited to that