Did you know? … Here’s 10 facts about Marilyn Monroe’s famous “Happy Birthday” serenade for President Kennedy.

Catch the next episode of The Garden’s Defining Moments  Saturday on MSG at 10:30 PM.

1. Although the occasion was held in honor of President John F. Kennedy’s birthday, it was also used as a Democratic Party fundraiser.

2. The event took place on May 19, 1962, 10 days before Kennedy’s actual birthday on May 29, when he turned 45.

3. Marilyn was working on the film “Something’s Got to Give” and took a break from fiiming to attend the gala. The movie was actually never finished and was Monroe’s last work.

4. New York Governor Robert Wagner and United States Vice President Lyndon B. Johnson were in attendance.

5. First Lady Jacqueline Kennedy was not in attendance.

6. The Star Spangled Banner was sung by Robert Merrill. Other famous celebrities who performed or spoke that night included Ella Fitzgerald, Maria Callas, Peggy Lee, Danny Kaye, Jack Benny, Henry Fonda, Jimmy Durante, Eddie Jackson, Bobby Darin, Mike Nichols, Elaine May and Peter Lawford, who at the time was JFK’s brother-in-law.

7. Monroe’s makeup artist and friend Marie Irvine had to convince security guards to let her in to Madison Square Garden to give Marilyn the earrings she had forgotten to bring.

8. Two months after Monroe’s famous serenade, she was found dead on Aug. 5, 1962 in Los Angeles. The famous movie star would never see the President again after the event at The Garden.

9. Monroe’s iconic dress was made by designer Jean Louis and originally cost $12,000.00. It was so tight that he would have to sew her into the dress.

10. In 1999, the dress was purchased for over $1.26 million at a New York auction.