Gareth is Katie and Jess's dad from the Holly Webb book Timmy in Trouble. When Katie comes back downstairs from brushing her hair and putting it in bunches, Dad winks at her as if he is joking, but hugs her and tells her that they'll be getting a puppy for Christmas (much to Jess's worry about Misty), and he and Katie look up puppies in the dog breed book to see what type of breed Katie wants.