Michael made his home in Groton since 1990. His career included mechanical design, accounting, and industrial radiography. His avocation was his interest in aviation and military aircraft. He raced motocross from an early age and continued as a senior rider. He was a very patriotic person, organizing â€œcare packages for overseas troops,â€ and he was a regular blood donor.
His survivors include his mother and stepfather, Mary and Donald Spigarelli of Groton; his father and stepmother Robert and Judith MacMillan of Bellevue, WA; brothers Robert T. MacMillan of Nashua, NH and Theodore P. MacMillan of Adams, MA; half brother Patrick MacMillan of Redmond, Washington; aunt and uncle Marjorie and Joseph Roozen of Bremerton, Washington; and loving nieces, nephews and cousins.