America’s mom, “Brady Bunch” star Florence Henderson, was suffering from a previously undisclosed cardiac condition when she died of heart failure on Nov. 24 at age 82.

Her death certificate, obtained by TMZ.com, noted Henderson had had heart disease for a decade and that five years ago she was diagnosed with an irregular heartbeat, the website said Tuesday.

The singer-actress — who became a television icon as Carol Brady, mother of a blended family on the 1969-1974 ABC sitcom “The Brady Bunch” and its spinoffs and sequels — had appeared to be hale and hearty three days before her death when she was in the audience of “Dancing With the Stars” on Nov. 21, cheering on her TV daughter Maureen McCormick in night one of the live, two-night season finale.

Henderson had appeared this year in the Marlon Wayans comedy “Fifty Shades of Black” and in an episode of the Disney Channel series “K.C. Undercover,” and she stars in the upcoming, independently produced dark comedy “Grandmothers Murder Club,” filmed in 2015.

She herself had competed on “Dancing With the Stars” in 2010, dancing with Corky Ballas and remaining in the competition as four other celebrities were eliminated before her — even though, at 76, she was season 11’s oldest competitor and suffering from the undisclosed heart condition. Judge Carrie Ann Inaba called her a “sexy senior” for her final dance — a tango set to “The Brady Bunch” theme song — and Henderson told “Good Morning America” afterward, “I just can’t help it. . . . It just oozes out of me,” adding playfully, “I’m bringing sexy back, and that’s all there is to it.”