From my experience, which is pretty limited, I'd say they would be pretty mediocre together. I mean, Perch are pretty good, aggressive predators themselves and having two such species in one very small pond might prove very difficult to manage. I have always heard of Perch being refered to as pond companions of Walleye and/or Smallies. You might want to try a Perch only pond if your concern is only for your sons. You'd probably have to do a good selective harvest as Yellow Perch are great spawners and can easily stunt in a small pond.
