thanks, everyone. I fell asleep with her in a blanket with me, and, then, put her to bed. When I woke up a few hours later, she'd pooped a little and moved a little out of the spot I'd put her in, but, she'd died. She was still really warm and her little toes and limbs were still flexible, so, it had happened shortly before I'd woken up. I'm taking her to the vet today. She's at the bridge with my other rats, Gwynnie and Lily.