My friend has a guinea pig and she is 14 (pretty old for a guinea pig) but they had 2 others that lives about 10 and 12 years. 5-10 years...the longest ever lived is 17 years.

I am 14 and 5 feet 3 inches and I weigh about 109lbs and I am very healthy and I'm in a lot of sports. I hope that helps. It varies from person to person but I am a very healthy girl and the right weight.

My friends chihuahua got her period when she was 2months old. But it varies between dogs and they types. Usually within 6 months.