Mark passed away at his home in Kent, WA after a battle with lung cancer. He was born in Seattle, Washington, to Shirley and Robert Prothero. He graduated from Renton High School, the University of Washington, and the University of San Diego School of Law.

Mark lived a life of giving to others, primarily through work as a defense attorney, devotion as a swim coach, and advocacy for the Kent community. His true love was his family. Mark is survived by his wife Kelly, son Sean, daughter Marley, mother Shirley, and brother Blake.

There will be a Celebration of Life on Saturday, May 10 at the Kentwood High School Commons, 25800 164th Ave. SE, Covington, WA 98042, from 1-5 PM. It will be an open house. In lieu of flowers, the family requests donations to the Husky Swimming Foundation or the Kent Parks Foundation. -