person A: I have a stuffed animal that my old dog used to lay by/on as a pillow. My dog is dead but I still keep that stuffed animal to remind me of him
person B: I am sorry your dog passed away_comma_ I totally understand wanting to keep a momento to remind you of him. Was he old when he passed?
person A: He was about 12.  He was my first dog though! He was a sweetheart.  It is nice keeping something to remind me of him.
person B: I'm glad you have something that helps keep his memory alive. :)
person A: I do too! 