Sometimes it's just genes. We have three adult Ruddy Abys in the family. An 18-month old female weighs almost 6 pounds. An adult 3 year old male is just over eight pounds and an 8 year old male weighs in at 12 pounds. We also have a 3 year old female Tabby since she was born who weighs 6 pounds, 4 ounces. All are exceedingly active and healthy.