Thanks, guys! She really did crawl into my heart pretty fast. I mean, I knew the chances of her being sick were VERY high since the rest of the rats she was with were very sick. The necropsy we did on the other rats showed serious lung and liver lesions. So, after seeing that, I really knew that my chances of keeping Sienna alive were slim. But I still wanted to give it everything I had. The vet at school gave me antibiotics and fluids to give to her but none of it worked. I think the stress of trying to treat her is what finally pushed her over the edge.

I remember a couple days before she died, I was scritching her ear and she really loved it. She made this chirping noise, and I wasn't sure exactly what that meant, so I stopped. She pushed her head forward as if to say, "c'mon! keep doing it!" so I did it again. She had her eyes closed and seemed to be really enjoying it. That's when she crawled into my heart. It made it even harder to see her go a few days later.
But now I'm in the process of getting two ratty babies. Unfortunately, the litter that I was planning on getting them from had a couple of the females die. I was in line to get two females, but now I would only be able to get one (which won't work out since I don't have a rat home already). The breeder showed me the next litter that she's planning in March -- the mom and dad are both two absolutely adorable dumbo-eared rats. I think that the babies from them would be breathtakingly cute. So I'm asking the breeder if I can hold off and be at the top of the pick list for babies from that litter. I'd been out rat toy shopping and have some stuff waiting for the new babies so I guess I'll just have to wait a little longer.