The Dumping Ground
Joseph first appears in the episode It Takes Two. In Episode 18, How To Be Perfect, Joseph places a note in Bailey's room saying that he has taken Mischief because Bailey laughed at Tyler when he said that he was practising dancing. After looking for Mischief when he escaped from the shed, Joseph finds that Bailey has taken Joseph's bike. They eventually return both items to the rightful owners.
In Season 5, it is shown that Joseph has a deep interest in space, when he and Finn break into an observatory to use a real-life telescope to see the moon more clearly. The professor at the observatory signs Joseph's book of the universe for him.
Joseph is portrayed to be a quiet, laid-back resident of the Dumping Ground. He also seems to like doing chores, as when Mike told Tyler to wash the floor, Joseph insisted that he'd do it, even though he was sorting out the residents' shoes at the time.