Happy birthday William Daniels, aka Mr. Feeny! Everyone’s favorite strict but lovable high school-turned-college professor celebrates his milestone 99th birthday today, March 31, and he’s already expressing his gratitude for his illustrious life and career. “I think the most important thing you should know is that I am very lucky,” he told TODAY.com on his birthday. “I’ve been able to work and keep active and have a sense of purpose. I was on Boy Meets World until I was 73 years old!” He also gushes about the chance to spend his birthday with his sons and especially his wife of nearly 75 years. Take a deeper look at William and actress Bonnie Bartlett’s (legitimately historic) marriage… © Getty Images Who is Bonnie Bartlett? Bonnie Bartlett Daniels, now 96, is an actress as well, with a career that spans nearly seven decades. She made her screen debut in 1955 playing Vanessa “Van” Dale Raven Sterling in the soap opera Love of Life, a role she inhabited until 1959. She then played the recurring character of Grace Snider …