Thanks for your comments. I also read your note on jealousy. Funny, you know exactly what they're like without even having seen then! Has Casper always been on his own, or has a mate of his recently passed away? Do you have any other rats?
It's good fun to be speaking with someone all the way in Arizona. I am originally from South Africa. My whole family are still over, but I am quite happy here for now.
What's Casper's personality like? Did you have him since a baby? Pet Shop or Breeder? Has his character changed much from baby to adult?