I've got pet rats: 2 adult males and 2 adult females + 10 babies. My little black and white mama rat had 13 babies 2 weeks ago and now there are 10. They are just opening their eyes and they are so cuute.
You would be amazed at how many people will say pet rats are disgusting but they are usually very friendly. They don't pee on you as much as mice do. I used to have mice but the summers up here are too hot for them unless you have airconditioning (which I don't). Rats seem to be more hardy.
I wanted to get a guinea pig when I was little and even arranged with a friend at school to get one. Unfortunately, I was out when it arrived and only dad was at home and he got really angry and told the girl to take it back.
_________________
Break out you Western girls,
Someday soon you're gonna rule the world.
Break out you Western girls,
Hold your heads up high.
"Western Girls" - Dragon