Madonna Shares Sweet Photos of Twin Daughters as They Celebrate Their 9th Birthday: 'Grateful'

Madonna/Instagram; Inset: Kevin Mazur/Getty

Madonna is showing her love for her twin daughters as they celebrate their birthday.

On Tuesday, the pop icon paid tribute to her twin daughters Estere and Stella with a sweet series of photos on Instagram in honor of their 9th birthday.

Madonna shared several photos of her girls at various ages, including a recent picture of the twins with their mom from the singer's 63rd birthday party. The artist welcomed Estere and Stella via adoption from Malawi in February 2017.

"Happy Birthday Stella and Estere!!!! 🎂🎂🎉🎉🧨🧨💃🏿💃🏿🍕🍕🎁🎁❤️‍🩹❤️‍🩹🔥🔥," Madonna writes. "2 Beautiful Souls……….who bring nothing but Joy to everyone they meet. 🙏🏼. So Grateful to have them in my life. ♥️💙💜💗🖤💛💚💖❣️💕"

Watch: How Madonna Became The Queen of Pop

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

RELATED: Madonna Poses with All 6 Kids at Birthday Party While Celebrating with Boyfriend Ahlamalik Williams

Madonna is mom to sons Rocco Ritchie, 21, and David Banda, 15, whom she shares with Guy Ritchie; daughter Lourdes Leon, 24, whom she shares with Carlos Leon; plus daughter Mercy, 15.

Last week, the "Like A Virgin" artist shared photos from her birthday bash, where her boyfriend Ahlamalik Williams and all six of her kids made an appearance.

Ricardo Gomes

She called it a "6th century eXtravaganza," and in one post, she included a family photo in a gallery of snapshots with everyone in different outfits for the occasion, writing, "Under the spell of the Byzantine Empire . ………….. 🍒🍋🍊🍉🍇🍎✝️."

Back in 2017, Madonna offered fans a rare look into her personal and family life for a PEOPLE cover story, months after welcoming her twin daughters.

"It's inexplicable," she said at the time of what drew her to her children. "It's like saying, 'Why do you fall in love with the people you fall in love with?' You look into the eyes of somebody, you feel their soul, you feel touched by them — that's it."

"Sometimes I would just close my eyes and just think, 'Why isn't my kitchen filled with dancing children?' There's so many children that need a home," she recalled at the time. "I thought, 'What am I waiting for? Just do it.' "

The musician also opened up about how her older children adapted to their expanded family at the time. "There might have been [a feeling of], 'Oh, we have to share you with more people' — not jealousy, but an adjustment," said Madonna at the time. "Eventually everyone was supportive. Lola said, 'Mom, if that's what you want and it's going to make you happy, let's go.' "

Watch: Madonna asks for donations to her Malawi hospital as her birthday gift