Story highlights Doctors diagnosed Annette Funicello with multiple sclerosis in 1987

In the '50s, Funicello quickly became the most popular Mousketeer

Walt Disney discovered her dancing the lead in "Swan Lake" at age 13

Funicello starred with Frankie Avalon in early 1960s beach party movies

Annette Funicello, one of the best-known members of the original 1950s "Mickey Mouse Club" and a star of numerous 1960s "beach party" films, died Monday at a California hospital, the Walt Disney Co. said

Funicello, who was 70, "died peacefully from complications due to multiple sclerosis, a disease she battled for over 25 years," the Disney statement said.

"We are so sorry to lose Mother," her three children said in a statement. "She is no longer suffering anymore and is now dancing in heaven. We love and will miss her terribly."

Funicello was just 13 when she was selected by Walt Disney himself to be one of the original Mouseketeers of the "Mickey Mouse Club," the 1950s television variety show aimed at children.

Funicello, who had a background in dance, quickly became one of the most popular Mouseketeers.

JUST WATCHED Legendary Mouseketeer Funicello dies Replay More Videos ... MUST WATCH Legendary Mouseketeer Funicello dies 03:22

JUST WATCHED Paul Anka reveals source of 'Puppy Love' Replay More Videos ... MUST WATCH Paul Anka reveals source of 'Puppy Love' 04:14

Photos: Remembering Annette Funicello Photos: Remembering Annette Funicello Remembering Annette Funicello – Annette Funicello , here in the mid-1950s, became famous as one of the original Mouseketeers on "The Mickey Mouse Club." Funicello, 70, died Monday, April 8, at a California hospital of complications from multiple sclerosis, the Walt Disney Co. said. Hide Caption 1 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello and Jimmie Dodd promote "The Micky Mouse Club" in 1957. Walt Disney selected Funicello to be on the popular children's show when she was 12. Hide Caption 2 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – '"American Bandstand" host Dick Clark interviews Funicello in the mid-1950s. With a background in dance, she quickly became one of the most popular Mouseketeers.

Hide Caption 3 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – The actress, here in 1960, also appeared in several "beach party" movies. Hide Caption 4 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello and Frankie Avalon, here in 1962, co-starred in several films together, including "Beach Party," "Muscle Beach Party" and "Bikini Beach." Hide Caption 5 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – That same year, Funicello and Paul Anka don buttons that read, "KHJ Radio 93 Salutes Elvis." Hide Caption 6 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello dances with her first husband, agent Jack Gilardi, at their wedding reception in 1965. Hide Caption 7 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello and Avalon appear in "Beach Blanket Bingo," shown at a drive-in movie theater. Hide Caption 8 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Avalon and Funicello reunite for "Dick Clark's Good Old Days Part II," a 1978 TV special. Hide Caption 9 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello is at the 1992 Disney Legends Awards at Walt Disney Studios in Burbank, California. Hide Caption 10 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello gives Mickey Mouse a kiss in 1993 after receiving a star on the Hollywood Walk of Fame. Hide Caption 11 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello and husband Glen Holt attend a gala in New York. Hide Caption 12 of 13 Photos: Remembering Annette Funicello Remembering Annette Funicello – Funicello chats with Avalon, right, and Fabian during an event in 1997. Hide Caption 13 of 13

She "was and always will be a cherished member of the Disney family, synonymous with the word Mouseketeer, and a true Disney Legend," Disney chairman and CEO Bob Iger said.

She remained with Disney after leaving the "Mickey Mouse Club," appearing in TV shows including "Zorro" (1957), "The Nine Lives of Elfego Baca" (1958) and starring in the Disney feature films "The Shaggy Dog" (1959), "Babes in Toyland" (1961), "The Misadventures of Merlin Jones" (1964) and "The Monkey's Uncle" (1965).

The most enduring images of Funicello, though, may be of her in a swimsuit, her primary wardrobe when she co-starred with teen idol Frankie Avalon in beach party movies in the early 1960s. These included "Beach Party" (1963), "Muscle Beach Party" (1964), "Bikini Beach" (1964), "Beach Blanket Bingo" (1965), and "How to Stuff a Wild Bikini" (1965).

Although she started out in a more modest version, each movie revealed a bit more, leading eventually to Funicello in a bikini.

The movies helped sell her music. Funicello had Top-40 hits including "Tall Paul," "First Name Initial," "How Will I Know My Love," and "Pineapple Princess." Along with the singles, she recorded several successful albums, including "Hawaiiannette" (1960), "Italiannette" (1960) and "Dance Annette" (1961).

Funicello reunited with Avalon in 1987 to star in "Back to the Beach," in which the two former teen idols played as parents of a pair of troublesome teenagers. Avalon and Funicello followed the movie with a nostalgic concert tour in 1989 and 1990, singing their hits from the 1960s.

"We have lost one of America's sweethearts for generations upon generations," Avalon said of her death. "I am fortunate enough to have been friends with Annette as well as appear in many films, TV and appearances with her. She will live on forever, I will miss her and the world will miss her."

"She will forever hold a place in our hearts as one of Walt Disney's brightest stars, delighting an entire generation of baby boomers with her jubilant personality and endless talent," Iger said in a statement released Monday. "Annette was well-known for being as beautiful inside as she was on the outside, and she faced her physical challenges with dignity, bravery and grace. All of us at Disney join with family, friends, and fans around the world in celebrating her extraordinary life."

Funicello moved with her family from her birthplace of Utica, New York, to Los Angeles when she was 4.

Walt Disney saw her dancing the lead in "Swan Lake" at the Starlight Bowl in Burbank when she was 13. Disney asked her to audition for a new children's TV series he was developing called "The Mickey Mouse Club." She was hired on the spot to become a Mouseketeer, Disney's statement said.

She became the viewers' favorite soon after the show debuted in October 1955. Although only three original seasons were produced, the show continued to be see in reruns for another four decades.

Doctors diagnosed Funicello with multiple sclerosis, a degenerative neurological disease, in 1987. She kept the illness a secret until 1992, the year she established The Annette Funicello Research Fund for Neurological Diseases. The charity, which is still active, supports research into the cause, treatment and cure of multiple sclerosis and other neurological diseases.

Funicello made few public appearances by the late 1990s as she became more debilitated by the disease. She lived under the care of her second husband Glen Holt, a rancher she married in 1986.

She had three children -- Gina, Jack Jr. and Jason -- from her first marriage to Jack Gilardi, which ended in 1981.

"It hurts me deeply in the passing of Annette," Jack Gilardi said. "She was such an important love in my life and blessed me with three beautiful children. I will remember her always and she will live in my heart forever."

"It is so sad to lose a wonderful lady like Annette Funicello," said comedian Don Rickles. "I had so much fun working with her in those beach party pictures. She was a great trouper. My wife Barbara and I send our thoughts and prayers to her family."

"Annette's sweet, unassuming spirit, her love of people, and her capacity to exude kindness and good feelings to everyone she met was part of her beautiful charisma, said Richard Sherman, the Oscar-winning composer who wrote many of her hits. "Because the songs we wrote for her brought us to the attention of Walt, Bob and I always referred to Annette as our 'lucky star.'"

Paul Reubens, who worked with Funicello and Avalon in a memorable appearance on Pee-wee Herman's Christmas special in 1988 and in "Back to the Beach," tweeted about her death: "I loved Annette Funicello from the 1st time I saw her on The Mickey Mouse Club. There wasn't a warmer, lovelier person on the planet. RIP"