Authority Kitten to Pro Plan Adult

So some of you may remember Jack and Dash... Well it is Dash's one year birthday today and that means jack is at 10 months. I was trying to move them from authority to pro plan adult at a 50/50 mix. Dash usually has the tempermental stomach, but it appears that he is doign fine, while jack is throwing up a little bit, and has some diaherria. Is that normal?

Thanks!

I would back off on the ratios a bit...i.e. start with 20/80 or something like that and move slowly. If Jack still has trouble at that rate, then it may be time to look at a different food.

but they love salmon!!!