If you want some rodent to take care of I'd go with rats. I've raised up several pet rats and I think they're much nicer than mice. They're stinky too though, but you can train them to do cool tricks. My very first pet rat was a feeder rat that my mother wouldn't let me feed to my snake. Lived to a good ripe age too. But I'd say a mouse isn't the way to go. Much love, I know it's tough and there will always be a spot in your heart for your loss, but sometimes there is nothing you can do. My best wishes to you <3