A Waggily Tale

 A Waggily Tale is a 1958 Looney Tunes cartoon.

Plot
 A boy named Junior, who treats his dog, Elvis, cruelly, is scolded by his mother and sent to his room to have a nap. Junior dreams that he is a dog adopted by a loving little girl, who doesn't know that dogs aren't supposed to be washed in a washing machine, or bandaged from head-to-toe after being beaten up by a scrappier, smaller dog, or toothbrushed with shaving cream. Junior awakes from his dream in shock. Now sensitive to his own dog's feelings, Junior vows to be nicer to him.