“On Mother’s Day I am also thinking of my TV mom too!” McCormick captioned a photo of the two stars. “She was a mother to so many all over the world! And she spread her love and laughter wherever she went! Love and miss you Flo!”
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Henderson died surrounded by friends and family at Cedars-Sinai Medical Center in Los Angeles after suffering heart failure, her manager Kayla Pressman said in statement at the time. She was hospitalized just a day prior.
McCormick, best known for her role as Marcia Brady in the hit sitcom, previously opened up exclusively to PEOPLE about the time she spent with her beloved friend and costar.
“I first met her when I was just 12 years old,” she recalled. “At the time she was like a second mother, but she was so much more than that. She became a dear friend.”
“I spent so much time with her on weekends at her house with her family,” she added. “Her kids became almost siblings — and all of them are such beautiful people today, which is such a testament to Florence.”
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According to McCormick, anyone Henderson met “became family.”
“She embraced everyone,” she said. “She had incredible love for everyone and wanted to spread that joy and light and laughter wherever she went. The song’s words could not have been more true — she was one of the loveliest ladies I’ve ever known.”