John Patrick Tetzlaff Sr., age 83, passed away Friday, January 25, 2019. He was preceded in death by his parents, Leonard and Anna Tetzlaff; and sisters, Helen Staal and Betty Haight. John is the beloved father of Linda (Paul Luna) Young, Laura Mosteller, Kathleen Tetzlaff, Kimberly Horsley, and John (Dawn) Tetzlaff. He is dearly loved by his 16 grandchildren and 13 great-grandchildren. He is also survived by his sisters, Peggy Peless, Alice (Eugene) O’Dowd and Ann (Rich) Scholten. John was a commercial painter for Kooi Industrial Painting for many years. Memorial Mass of Christian burial will be celebrated Thursday, January 31, at 11:00 a.m. at St. Mary Catholic Church, 402 Amity St., Lowell. Rev. Aaron Ferris presiding. The family will greet friends and relatives one hour prior to the mass at the church.