Michael E. "Mike" Kertis, Sr., age 83, of Warren County, PA. passed away in Wilmington, DE surrounded by his family on Thursday, November 30, 2017.Raised in Sutersville, PA, son of the late Louisa Weimer and Michael Kertis. He graduated from Bucknell University in 1957 then served in the US Army.Mr. Kertis taught the sciences at both Ridley Park and Ridley High Schools. After 30 years he retired from teaching and established a carpentry business.In addition to his parents, he was preceded in death by his sister, Dorothy King. Mike is survived by his children; Michael E. Kertis, Jr. (Karen Nigro) of Fairfax, DE, Jennifer Kertis-Simmons (Rick Iorii) of Wilmington, granddaughters, Gabrielle and Olivia Simmons, sister, Lillian Markle, nieces, nephews and companion Margaret Pontoriero.Services will be private and held at the convenience of the family.