BEHIND her megawatt smile and glittery gown, CARRIE ANN INABA was hiding a painful secret from “Dancing with the Stars” viewers during the show’s March 18 premiere.

Her beloved father – 73-year-old Rodney Yoshimitsu Inaba – had died just days earlier after a brave battle with tongue and colon can­cer.

Sources say the Hawaiian tour operator suffered two heart attacks during his final years, but he coura­geously soldiered on.

“CARRIE ANN WORE A BLACK dress to honor the memory of her father, and it was all she could do to hold back the tears,” said an insider. “But she decided that being there was what her father would have wanted. Now, she’s decided to dedicate the rest of the season to him. And she’s thinking about performing a dance routine on the show in her father’s memory.”

Car­rie Ann wrote that her dad, nicknamed “Uncle Rod” on the Big Island, “had a huge heart and an unfiltered mouth, and that made for a wonderful adventure called life.”

This isn’t the first time the 45-year-old “DWTS” judge’s fam­ily has been plagued by cancer. In 2008, Carrie Ann’s mother, now 73, was diagnosed with Stage 3 breast cancer.

“She was devastated,” said the insider. “Her whole world came to a crashing halt. She knew the statistics, and was worried that her mom wouldn’t make it. But after a mastectomy, chemo­therapy and radiation, she did. Sadly, her father was not so lucky.”

Although it was a tough deci­sion to appear on the “DWTS” premiere, Carrie Ann got through it like a champ before heading to Hawaii to say her final goodbye to her departed dad.

She shared with fans: “In honor of my father, I chose to do the first show…because in my heart, I know he would have wanted it that way.”