John Martin Castellanos Sr., devoted husband, father, grandfather, veteran, firefighter, and friend, passed away on October 20, 2026, in Zephyrhills, Florida, at the age of 74. Born on April 8, 1952, at Riverside Hospital in Toledo, Ohio, John lived a life defined by service, dedication, friendship, and love for his family.

John was born to Jesse Castellanos and Judith Castellanos (Walters) and was one of four brothers, growing up alongside Jesse "Mickey," Tom, and Robert "Chico." He graduated from Whitmer High School in 1970 before proudly serving his country in the United States Army from 1971 until 1975.

Following his military service, John married the love of his life, Diane Homer Castellanos, on November 15, 1975. Together, they built a remarkable life and shared more than five decades of marriage filled with love, laughter, and unwavering commitment. They raised three children, John II ("John Boy"), Brent, and Sara, who were the pride and joy of his life. In 2015, he welcomed his granddaughter, Zoey, whose arrival brought him immense happiness.

John and Diane made their home in Toledo, Ohio, until relocating to Millbury in 1991. There, John continued his lifelong commitment to serving others by joining the Lake Township Fire Department as a volunteer firefighter. Through years of dedication and leadership, he earned the rank of Captain before retiring. John also enjoyed a distinguished 30-year career at the BP Oil Refinery in Oregon, Ohio, where he was respected by coworkers and friends alike.

After retiring, John and Diane fulfilled their dream of moving to Arbor Oaks Mobile Home Park in Zephyrhills, Florida, where they spent many happy years surrounded by friends, neighbors, and countless cherished memories.

John was a man of many interests and passions. An avid collector, he was especially fond of antique automobiles and spent many years as a proud member of MARC and VMCCA. He loved attending car shows, sharing stories with fellow enthusiasts, and preserving pieces of automotive history. He was also an enthusiastic camper and a dedicated supporter of Scouting, serving as a Scout Leader with Boy Scout Troop 160 in Millbury, Ohio.

Perhaps more than anything, John will be remembered for his generous heart and welcoming spirit. He never met a stranger and had a unique ability to make people feel comfortable and valued. Whether through his service as a soldier, firefighter, Scout leader, coworker, neighbor, husband, father, or friend, John touched countless lives with his kindness, humor, and willingness to help others.

John was preceded in death by his parents, Jesse and Judith; his brother, Jesse "Mickey" Castellanos; and his nephew, Jesse Castellanos. He is survived by his beloved wife, Diane; his children, John II, Brent, and Sara; his granddaughter, Zoey; his brothers, Tom and Robert "Chico" Castellanos; and many nieces, nephews, extended family members, and friends.

A Celebration of Life will be held on November 29 from 2:00 p.m. to 5:00 p.m. at Lakewood Place, 28410 Oak Street, Millbury, Ohio 43447.

In lieu of flowers, the family kindly requests that donations be made to Boy Scout Troop 160 of Millbury, Ohio.

John's legacy lives on in the family he cherished, the community he served, and the many friendships he formed throughout his life. He will be deeply missed and lovingly remembered by all who had the privilege of knowing him.