Maralee Nichols celebrates her and Tristan Thompson’s son Theo’s 2nd birthday with train party

Maralee Nichols and Tristan Thompson’s son, Theo, is 2!

The toddler’s mom rang in his birthday by sharing train-themed party pictures on Monday.

Nichols and the little one matched in overalls, white long-sleeve shirts, red bandannas and striped conductor hats for the festivities.

The personal trainer showed off the bash’s decor via Instagram Stories, including Chugga Chugga Two Two balloons.

Nichols also shared a sweet snap of the birthday boy hugging her legs.

She welcomed Theo in December 2021, one month before Thompson, 32, confirmed his paternity.

Not only was the NBA player dating Khloé Kardashian at the time, but the duo were expecting a son named Tatum together via surrogate.

The on-again, off-again couple are also the parents of daughter True, 5. Additionally, the power forward and his ex-girlfriend Jordan Craig share son Prince, 6.

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While the athlete has yet to publicly acknowledge Theo since his arrival, Nichols has posted frequent updates with her baby boy’s milestones over the years.

For his 1st birthday last year, the proud mom called Theo her “greatest blessing.”

She gushed, “Spending the past 365 days with you have been the best days of my life. You are the sweetest little boy, your smile brightens up any room.

“You are … my world, my heart in human form,” Nichols continued in the January 2022 Instagram tribute. “God knew I needed you. I love you more than anything. Happy 1st Birthday to my angel.”

The following month, she told her followers that Theo was “walking everywhere.”