Baby mouse died suddenly.

Question
Hi!  On Saturday (1/16/16) I found a baby mouse laying outside on the pavement.  She had full fur but her eyes were not open yet.  I brought her in and began feeding her KMR on a small paintbrush every 2 hours, assuming she was in the 1-2 week range.  Two days after I found her, she opened her eyes.  She was very energetic, ate great, made normal bowel movements, and seemed to be doing really well.  I had a small heater in the room and kept it between 75-80 degrees.  Fast forward to last night at 1130PM when I am doing one of her feedings and she is seeming pretty normal, she ate good.  I go in 3 hours later for another feeding and she was laying flat on her stomach with her eyes open.  I went to pick her up and it was almost like she was paralyzed.  She couldn't move at all.  I tried to feed her but she refused and I just knew she wasn't going to make it.  I held her as she convulsed every few minutes and eventually she passed.  

I am incredibly upset as I feel I did my best, I know raising infant mice is an extremely difficult task.  I just feel like I need some reassurance that I didn't do something wrong and this was going to happen anyways.  Would like to know if you had any idea as for a cause behind it.  

Thank you
Aubrey

Answer
Hi Aubrey,

I am sorry that I made you wait for a response.  My family and I have been sick - I know it's no excuse when you're sitting there worrying about your lost mouse, but I promise I did not ignore you on purpose!

You're right - raising baby mice is a tough challenge even for those very experienced in it.  From what you've told me, you are not at fault in ANY way.  The thing about orphaned mice is that you just don't know what is going on before you find them - sometimes they've been dropped from a predator or a piece of equipment.  Sometimes moms kick them out of the nest when they know they have some kind of health problem or internal defect.  Some mice are even born with lethal genetic conditions that mean they only live 2-3 weeks.  There is simply no telling.  The only thing we can do as caregivers is give them a good home while they are with us and a lot of love - but we can't always keep them alive if their time is up.

That good home is exactly what you gave her.  That pup is lucky to have had you for the time she was alive, and that is all that matters.  Thank you for putting your time and heart into her, and I am sorry for your loss.

Best wishes,
-Tam