Story:

“In my family, we believe that when a person dies, they become a dove.  When my great-aunt and grandfather died, the next day there were two doves in our backyard.  So I believe it.”

My informant thinks this is because the dove is often associated with souls that fly up to heaven.

The Mourning Dove is often symbolic of optimism and is spiritual with a message of life, hope, renewal and peace.  This is very helpful for a family that is coping with the death of a beloved member.  There are other tales of loved ones becoming butterflies or ladybugs. It is typically an animal that can fly and is very beautiful, which is similar to the idea that the soul of a loved one is beautiful and flies up to heaven.