A friend of mine took her puppy to the vet, and he found that, so far, he only has one testicle that has descended. None of the males in his past five generations, on both sire and dam's pedigrees, have this problem, and most are Champions, as is his sire. My question is, how common is this, and how long does it usually take for the other testicle to descend (if ever)? Since there is no evidence of a hereditary issue, do some dogs just suddenly develop this trait, or could it be that it's just something that will work itself out, so to speak? Thanks in advance for the advice!