Beneath his mother's white-gloved glamour was a parent who brought her kids (Albert and his sisters, Caroline and Stephanie) to the Jersey Shore, wore turbans to "hide a bad hair day," and encouraged party guests to plunge into the palace pool after a private reception for the Monte Carlo ballet. (She jumped in after Rudolf Nureyev.)
Despite growing up amid such palatial splendor (Frank Sinatra and Cary Grant were frequent guests), Albert, 56, says, "Our parents made sure it felt like a normal home. Not palace-y." That meant a mom who did such homey things as planting corn kernels (brought back from the U.S.) in the backyard so they could eat it off the cob (unheard of in posh Monaco.)
It's now been 32 years since the car Grace was driving careened off a cliff, killing her at 52. And her son wants to dispel many of the myths that surround her.
Although she never made another movie after moving to Monaco, Albert says, "Deep down, she would have loved to have played the role in Marnie" – Alfred Hitchcock had offered it to her – "but she knew her duties and her commitment to her family were more important."
"Those were the circumstances. My father never obliged her to give that up or say no to Hitch. He said, 'Listen, it's your choice. Of course, I need you here, and if you think that is what you want to do, then I'll accept that.' He said it was up to her."
Asked if he thinks she would ever have returned to Hollywood, he says she once told him, "But the movie business has changed so much since I was there."
Albert last saw his mom the morning of Sept. 14, 1982. "I'd slept in a bit," he says. "She kind of poked her head into my room as she was about to leave with Stephanie to drive down the mountain from our country house."
"And she said, 'Okay, I'll see you later.' And that was the last time I saw her." Her death, he adds, was "a huge shock. I wanted to talk to her and about a lot more things. I wanted her to be here at other moments."
Honoring Her MemoryStill, she lives on in her movies and his memories. One memento he treasures is a plaque that his mother gave him for his 21st birthday, engraved with the Rudyard Kipling poem "If."
"It's basically advice for a young man to overcome different obstacles in life and if he does overcome them, then he be called a man," says Albert, blinking back a few tears. "That still resonates pretty deep."
The prince and his wife, Princess Charlene, 36, who are expecting a baby in December, will be in Los Angeles for the Princess Grace Foundation USA gala on Oct. 8.
Founded by Prince Rainier after her death, the foundation has given over 800 grants, totaling over $10 million, to artists in theater, dance and film – a continuation of Grace's love for the arts. This year's gala, sponsored by Dior Haute Couture, will honor Dick Van Dyke and feature such celebrity guests as Jane Lynch (the night's emcee), and Reese Witherspoon and her husband, Jim Toth.
"She was a wonderful mother and a wonderful person," says Albert. "It was deeply engrained in her to help others."
For more on Princess Grace, pick up a copy of this week's PEOPLE, on newsstands Friday