However, guinea pigs do vibrate, and it's usually a sign of happiness or excitement. It's called "rumbling" or "purring" and is a way for them to communicate their positive feelings.
Here are some reasons why your guinea pig might be vibrating:
* Happiness: They might be happy to see you or to be getting treats.
* Excitement: They might be excited about playtime or getting some fresh hay.
* Contentment: They might be content and relaxed, enjoying a cuddle or a good nap.
If your guinea pig is vibrating excessively or seems distressed, it's best to consult with a veterinarian to rule out any health issues.