Kimora Lee Simmons Celebrates 'Amazing' Son Gary's 14th Birthday: 'So Lucky to Have You in Our Lives'

Kimora Lee Simmons is showering her son with love on his birthday.

On Monday, the entrepreneur, 48, shared a sweet tribute to son Gary on Instagram as he celebrated his 14th birthday. Sharing a carousel of photos of the two of them, Simmons smiles with her son, kisses him on the cheek and gives glimpses of his football-themed birthday party.

"Gary Lee!!! HAPPY BIRTHDAY to my football star, handsome, fly young man! You're an amazing brother, friend and incredible son and we're so lucky to have you in our lives!" the proud mom wrote in her caption.

"I'm so proud of you! We all love you soooo much! ❤️😎🎉🏈🎂🎁."

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Simmons is mom to five kids. She shares daughters Aoki, 20, and Ming, 23, with ex Russell Simmons, son Kenzo, 14, with ex Djimon Hounsou, and son Wolfe, 8, with Tim Leissner. She welcomed son Gary via adoption when he was 10 years old.

In August, Simmons took all five of her kids to Japan, telling PEOPLE that she was clear with her children from the beginning that they were there to experience their culture. "It was rewarding to expose all my kids to Japan," the entrepreneur told PEOPLE exclusively at the time.

"I've traveled there so many times throughout my life for work or modeling. Japan is vibrant, electric and such a vibe shift! Watching them absorb their surroundings — the art, the food, the language, the fashion — was beyond rewarding."

"We're so blessed. They're already asking when we can go back!" she added.

"Before we flew there, I was clear from the jumpstart: 'This is not a vacation! This is a cultural trip! It's educational. We're not lounging and shopping. We're broadening our experiences and taking in a culture."

"But yes, Japan is fly! And it's your heritage!" Simmons said of telling her kids about the trip.

As a single mom, Simmons has always strived to put her children at the forefront. She told PEOPLE in May: "I'm a single mom of five kids and I know how hard it can be and I don't want to start crying, but it's Mother's Day, I know how that feels like to raise your kids and to get up every day and only care about them."

She stressed that being a parent in any capacity was difficult, adding, "And it doesn't matter, if you're rich and famous or you're this thing or this singer, that singer, at the end of the day, you're a mom or you're a cousin, you're an auntie, you're a family member, you're a community person, a caregiver, you're just there trying to make everything come together."