"Even though Betty was about to be 100, I thought she would live forever," Witjas told multiple outlets in a statement.
"I will miss her terribly and so will the animal world that she loved so much. I don't think Betty ever feared passing because she always wanted to be with her most beloved husband Allen Ludden. She believed she would be with him again."
As the old joke goes, White herself was older than sliced bread. She was born on January 17, 1922 in Oak Park, Illinois. The sliced bread machine was not invented until around 1928.
White started her career in radio in the 1930s, before finding sitcom fame with The Mary Tyler Moore Show in the 1970s and Golden Girls in the '80s and '90s. She won eight Emmys in her career, and defied expectations on what it meant to be a woman in show business.
Just this week, PEOPLE released an issue celebrating Betty White's 100th birthday. In it, she revealed that her secret to longevity was the result of good health, good fortune, and her work.
"I'm so lucky to be in such good health and feel so good at this age," she told the magazine. "It's amazing." Of her diet, she hoked: "I try to avoid anything green. I think it's working."
She said being "born a cockeyed optimist" was key to her upbeat nature. "I got it from my mom, and that never changed. I always find the positive."
As well as becoming a pop culture icon, Betty White was an animal rights activist and LGBTQI advocate.
Her Golden Girls character Rose was "instrumental" in raising awareness of LGBTIQ issues, a statement from queer advocacy group GLAAD said, most notably in an episode about HIV in the early 1990s. She remained a queer icon for the rest of her life, using her platform to advocate for the community long before such issues became mainstream.
White was married three times, meeting her third and final husband, TV show host Allen Ludden, in 1961 on his game show Password, on which she was a guest. Ludden was the love of her life. She spoke of feeling like a failure for being divorced twice, and so she turned down Ludden first two proposals before saying "I Do" two years later. They were married until his death in 1981 from stomach cancer; she never remarried.