Melinda French Gates Makes Rare Appearance with Son Rory at White House State Dinner

The philanthropist and her son smiled as they walked arm in arm at the event on Thursday

Melinda French Gates brought a special date to the White House State Dinner: her son Rory.

The billionaire philanthropist, 59, attended the event arm in arm with her only son, whom she shares with her ex-husband Bill Gates, on Thursday, May 23. The date also marked Rory's 25th birthday.

For the occasion, Melinda smiled as she donned a spring-themed, floral, floor-length gown with a pastel yellow scarf draped around her shoulders. She completed her look with a matching yellow clutch.

Rory kept his look classic with a black suit, white button-up shirt, black tie and dress loafers.

Related: Bill Gates and Melinda French Gates Celebrate Daughter Jennifer’s 28th Birthday

About 500 guests arrived at the White House for the dinner honoring Kenyan President William Samoei Ruto and his wife, Rachel Ruto, according to the Associated Press.

Other arrivals include Brad Paisley, Don McLean, Democratic New Jersey Sen. Cory Booker, who brought his mother, and former Atlanta Mayor Keisha Lance Bottoms, who attended with her 16-year-old son.

LeVar Burton, former Presidents Bill Clinton and Barack Obama also attended. Former Secretary of State Hillary Clinton joined her husband as well.

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Related: Bill Gates and Melinda French Gates' Relationship Timeline

Melinda and Rory's night out comes after the family celebrated another milestone together.

On May 11, Bill and Melinda's eldest daughter Jennifer Gates, 28, graduated from medical school. The ex-spouses also share daughter Phoebe, 21.

Jennifer celebrated the accomplishment with an Instagram photo posing in her cap and gown.

In the comment section, Bill, 68, saluted his daughter, writing, "What you have achieved today—and every day leading up to it—is a tremendous accomplishment, @jenngatesnassar."

He continued, "I’m so proud of you for finishing medical school, and I can’t wait to watch you take this next step into residency. Your patients will be lucky to call you doctor."

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Phoebe marked the achievement with clapping emojis. Melinda commented, "Jenn, I am so proud of you—and you should be so proud of yourself! What an incredible tribute to your passion, intelligence, and hard work. Can’t wait to see where your next chapter takes you @jenngatesnassar!"

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