do a search on silvers, you'll get loads of info on pro's and con's,
my advice has always been DONT, but this year, I had an un-planned mating of silver to silver, my first reaction was to knock them on the head, but Im a softie with ferts and could'ent, out of the twelve kitts, i have one very tiny runt, that had to be brought into the house for 3 days tlc, but she's still going strong at nearly 4 months old, and holds her own against bigger siblings, although a hob from the same litter, and as small as her, was on deaths door for a while, got it too the vets and payed £50 ish for injectio