Seth Engle is the husband of Lisa Engle and the stepfather to Karen Brewer and Andrew Brewer. He has two pets (a dog Midgie and a cat Rocky) that he had when he married Lisa. Seth is tall and has a beard.
He grew up on a farm in Nebraska. At some point he was a camp counselor and used to play the bugle at sun up and sun down in Karen's Show and Share. He had met Lisa when she had called him about building some bookcases and other projects in the house. His father died in the book Karen's Grandad.
In Karen's Hurricane Seth had built a new bench for Stoneybrook Academy from the old oak tree that stood there. He had carved the top of the back with leaves, acorns, birds, and two small squirrels. Seth put a plaque on the back that said that it was presented to Stoneybrook Academy by Mr. Colman's second grade class.
He had his carpentry business in the same building for ten years and had to move in six weeks time in Karen's Unicorn. His new workshop is three blocks from their house.
- Has an old friend named James
- In earlier printings of the first few books in the series, Seth was called "Kendall" Lisa Engle was called "Sheila".
- He likes animals.
- His veterinarian is Doctor Selwyn and has taken Rocky and Midgie to her for years.