Theodor H. Horstmann

March 6, 1935 – May 6, 2026

Theodor “Ted” Horstmann, a devoted husband, father, grandfather, entrepreneur, and lifelong innovator, passed away peacefully in his sleep on May 6, 2026, surrounded by his loving family, following complications from Parkinson’s disease. He was 91 years old.

Born on March 6, 1935, Ted lived a life defined by curiosity, determination, and a deep commitment to both family and community. A proud graduate of Lehigh University’s Class of 1958, he carried forward a passion for engineering and problem-solving that would shape his professional and personal pursuits for decades.

Ted was married to the love of his life, Nancy Kerr Horstmann, for 63 wonderful years until her passing. Together, they built a life rich in adventure, love, and cherished memories. They were avid world travelers and especially treasured their time in Vieques, Puerto Rico, where they joyfully welcomed family and friends and became known for their warm hospitality and unforgettable gatherings.

An accomplished entrepreneur, Ted founded Wilmington Valve and Fitting, successfully growing the business before its eventual sale. He later expanded his impact internationally by developing global business opportunities for Ross Valves. A true innovator at heart, Ted held multiple patents and was constantly thinking, creating, and improving—from repairing his tractor to designing advanced pneumatic valve systems. His intellect and ingenuity were matched by his hands-on spirit and unwavering determination.

Ted was deeply committed to education and giving back to his community. Alongside Nancy, he was a lifelong supporter of learning and co-founded a school in Wilmington dedicated to helping children with special needs—leaving a lasting legacy of compassion and opportunity.

He is survived by his three sons: Erich (Maria) of Wilmington, Delaware; Carl (Joy) of Marion, Massachusetts; and Douglas of New Castle, Delaware. He also leaves behind five grandchildren and four great-grandchildren, all of whom brought him immense pride and joy.

Ted will be remembered for his sharp mind, entrepreneurial spirit, generous heart, and unwavering devotion to his family. His legacy lives on in the lives he touched, the innovations he created, and the family he cherished.

A private service will be held by the family. In lieu of flowers, donations may be made in Ted’s memory to a Parkinson’s disease charity.