Mr. Trapples is an old tattered teddy bear belonging to Fred Jones, Jr. which he has formed a strong attachment to. He speaks to it as if it were alive much like a child might talk to their stuffed toy, but it could also possibly suggest a mild form of Schizophrenia.
Scooby-Doo! Mystery Incorporated
After Daphne further rejected Fred and the gang, he dressed up Mr. Trapples to resemble her even using some of her hair. During the scuffle on the haunted house, the newest found puzzle piece was lost, but ended up lodged in the face of Mr. Trapples.