My brother gave me money to get two baby rats for Christmas this year. I picked out a tall cage with bars fairly close together like my Psychology teacher uses for the class rats, but the girl at the pet store convinced me to get a one-level, wider cage with larger spaces between the bars, but now my babies won't stay in! I woke up at 4:00 this morning to one of them crawling between my sheets. The other is missing altogether. Is there a way to keep them in their cage or should I go ahead and buy the one I intended to? And how can I find my little runaway?