Or have the inside testicle removed when he is older and leave the other one, even if you don't plan on breeding him. He will still be a male dog.
It makes me wonder why the females of such litter don't get a note on their pedigree/registrations. They after all will be carriers for this genetic problem.
D, adolescence big time
"If love could have saved you, you would have lived forever." RIP my awesome Wolfie Dog