Arthur's Pet Business & D.W., the Copycat

Arthur's Pet Business: Arthur wants a dog very badly but his parents will not allow him to have one until he proves he is responsible enough. Arthur starts his own pet business to prove he is responsible, which includes watching over the unfriendly dog Perky.
D.W., the Copycat: Arthur does not like to play with D.W. because she likes "baby" stuff and not the stuff he likes, so D.W. starts acting and dressing like Arthur and following him around, even into the bathroom. Arthur's friends start excluding him because they do not want D.W. around.