I don't think it is uncommon for them to choose just one toy that is special to them; one that they carry around everywhere or sleep with. Muffin had a little "doggie" that we called "Doggie" and she had it all of her life. It lasted through many, many washings and seam repairs. Doggie was threadbare in many places. We buried Doggie with Muffin. She loved Doggie so.
Kacee has adopted a doggie puppet. We named this doggie "Brutus" because it kind of looks like a Brute.
Anyway, she'll lay down on the floor next to him and many times she will use him for a pillow.