John Worth

is (presumably) Daphne Worth's father. He is a retired electrical engineer who has started teaching honors science at the local high school, as "sort of a guest teacher." Daphne and John are on somewhat awkward terms with each other. 

(We presume that John is Daphne's father based on his showing up at the top of the list of invitees to Daphne's and Tricia's Wedding.)