every fair is probably a little different. I used to show meat pens and single fryers when I was a kid in 4-H. You want them as close to 5 pounds without going over. all 3 must be the same breed and variety. They don't have to be from the same litter but I learned they'll have better conformation in relation in each other when there littermates. I've also found the best meat pens are from does who are only milking about 3-6 kits.