Maralee Nichols Shares New Photo as Her and Tristan Thompson's Son Theo Turns 8 Months Old

maralee thompson instagram

Tristan Thompson and Maralee Nichols' little boy is growing up fast!

On Tuesday, the 31-year-old model shared a new photo on her Instagram Story of baby boy Theo to celebrate him turning 8 months old.

The sweet snap shows Theo's legs and one of his arms. He wears a green onesie with his arm outstretched towards blocks that read "Look who is 8 months."

Theo is the first baby for Maralee and the third for the NBA player, 31, who is also father to 4-year-old daughter True Thompson with ex Khloé Kardashian — with whom he's expecting another baby via surrogate this year — and son Prince, 5, with ex Jordan Craig.

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courtesy Maralee Nichols

RELATED: Maralee Nichols Enjoys Day at the Zoo with Her and Tristan Thompson's 6-Month-Old Son Theo

In May, Nichols celebrated her first Mother's Day and paid tribute to her son on social media.

"Words cannot express how much I love you, being your mommy is my greatest blessing," she captioned the photo of herself holding Theo while wearing a floor-length dress. "You are my world."

"Happy Mother's Day to all of the amazing mothers out there," she added.

In February, Nichols revealed the special meaning behind her son's name.

"Theo, my little angel baby," Nichols said in a statement to PEOPLE at the time. "I named you Theo because it means, 'Gift from God.' "

"I had never been pregnant and had been told I might not be able to have children," she added. "I couldn't believe I was pregnant, when I saw you on the ultrasound and heard your little heartbeat I knew I would always protect you and keep you safe. I love you more than you'll ever know. You bring such joy and happiness into my life. My great blessing."

George Pimentel/Getty; maraleenichols/Instagram

The birth certificate, obtained by PEOPLE, first revealed Theo's name. In a statement shared with PEOPLE from Nichols, she added that the athlete was not named on the birth certificate "because he was not present at Theo's birth."

The NBA player first confirmed he fathered the baby in January, writing on his Instagram Story, "I take full responsibility for my actions. Now that paternity has been established I look forward to amicably raising our son."

He continued, "I sincerely apologize to everyone I've hurt or disappointed throughout this ordeal both publicly and privately."

Thompson later apologized to Kardashian, writing, "Khloé, you don't deserve this. You don't deserve the heartache and humiliation I have caused you. You don't deserve the way I have treated you over the years."

He added: "My actions certainly have not lined up with the way I view you. I have the utmost respect and love for you. Regardless of what you may think. Again, I am so incredibly sorry."

Thompson's latest cheating scandal played out on the premiere season of The Kardashians on Hulu.