One of my rats died yesterday and we’re still not sure what happened. We noticed one of her front paws had a bad scratch on it that looked fresh, at first we thought she was missing her hand entirely but it was still there just hurt. We also noticed a little bit of blood around her butt area. She was energetic and playful just the day before and we have no idea what happened but we found her in her litter box in her cage yesterday when we went to change their water. I’m seriously just so distraught and so worried she might’ve suffered and my heart just hurts so bad. I also feel so sad for her sister who’s alone now. She was only around 18 months and I just don’t know what to do.
Unfortunately sometimes sudden deaths like this happen. I'm sorry for your loss. It sounds like it might have been a stroke, heart attack or a burst internal tumor (though I think that would involve more blood). As for her sister, it is important that she doesn't remain alone.