Peter M. Thornton, 74, of Warren, passed away in his sleep on Sunday, September 14, 2025. Peter was born July 9, 1951, in Warren, the son of the late Jon and Amelia Mack Thornton. He was a 1969 graduate of Warren Area High School and then earned a Bachelor of Arts degree at Edinboro University. Peter worked as an orderly at Warren State Hospital in the Forensic Unit for over 20 years from which he retired. Peter was a single father who lovingly raised his daughter in a home that he had meticulously built by himself. He enjoyed playing pickleball, golf, and cribbage. Peter is survived by his daughter, April Lawrence and her husband, David, who was like a son; nephew, Matthew Kiser and Justin Thornton of Portland, Oregon; siblings, Leonard Thornton of Victoria, BC, Agatha Kiser of Youngsville, and William Thornton of Warren, and Rita Thornton of Warren. In addition to his parents, Peter was preceded in death by brothers, John, Guy and Adam Thornton; and sister, Grace Lamphier. Services for Peter will be private and held at the convenience of the family. Those wishing to send online condolences may do so by visiting www.petersonblickfuneralhome.com