Why does my dog carry her stuffed animal around constantly?

The crying is kind of confusing but the reason dogs love squeak toys isn't because the squeak gets them excited but because when the dog gets a small creature, lets use a squirrel for example, it has it's teeth around it and the squirrel let's out a highly pitched squeal before dying and thus, makes the dog feel better since it has dominated something. That's why dogs adore squeak toys. Now maybe the dog is sad about killing the "creature" XD, maybe that's why it cries.