<human>: I have been a dog owner for many years, and consider myself pretty well-informed.  For the last 10 days I have been taking care of a friend's Puggle.  When she got here, her dumps were really liquidy and she was a little too skinny for her size.  They have her on a new sensitive stomach food, but it's still the garbage grocery store brand and clearly not working.  

I know I shouldn't have crossed a line, but here's where I did.  I mixed some of my dogs' grain-free food with the Puggle's normal food.  Her next dump was better.  I did a little higher ratio.  Better still and she was acting less frantic.  Having gone through this before, I now know what her problem is and how to solve it.

The issue is that it's not my dog.  And the food that helped her is probably twice as expensive as the stuff they brought.  And to be honest, I don't know that they'd actually change anything anyways.  Do I bring this up?  Or is this like telling someone how to raise their kids?

Could you distill the essence of the text into 1-3 sentences?
<bot>: Watched a friend's dog, and her digestion got better when it ate my dogs' food.  Is it my place to suggest they change to this (more expensive) food?