Rats in my house :)

I have two pet rats in my house. They are very smart, intelligent, and dinky. I let them run around whole flat. Today they decided that under the armchair is a good place to play. They were very quiet and I couldn't find them for long time. It turns out that with rats it is like with kids- if you don't hear them that means they are roughhousing.

Smart and intelligent mean the same thing- do you mean two different things here?  And what do you mean by "dinky"?