
Hi Bettyboop (and Kate) Taking the last line of Kates reply first - he almost certainly IS capable of mating a bitch now, so if he is getting lots of procatice be meticulous about checking for seasons. Assuming you have now discovered that he has 2 normal testicles, and all health checks are done (especially heart) and parents are heart tested, you can consider using him at stud in the future. We like to get dogs first matings around 12 months of age - especially with a breed like a cavalier, who can be a bit wimpish. But do remember that it can change his whole attitude to life (note, Can not necessarily Will). He may territory mark, be more edgy with other males, and once he has learned the technique you will have to be even more vigilent if he lives with bitches.
Before being approached about this had you considered using im at stud? Is he your pet? How well do you know the bitches owner, what are her reasons for wanting to breed, are you sure the pups will be well reared and thought will go into homing them? As the studs owner, you are morally half responsible for the welfare of the resulting pups. Dont want to sound like a wet blanket, but there are an awful lot of Cavaliers out there - would you be adding something to the gene pool with your boy?
bye
Gwen