Time flies! Teen Mom OG star Maci Bookout shared a sweet birthday message to her son Bentley for his eighth birthday on Thursday, October 27.

The MTV docuseries star posted an Instagram photo of herself and her son at a pumpkin patch as they celebrated his big day and got ready for Halloween.

“Happy Birthday Bentley! We spent the day with his friends on a field trip to the pumpkin patch and then had an awesome dinner with friends and family!” she wrote.

“I can’t believe my baby is 8 years old, he has grown into an incredible young man, but he will always be my baby! I love you Bentley.”

Bookout, 25, also posted a message on Twitter, writing: “Happy Birthday Bentley! I can’t believe my baby is 8 YEARS OLD!”

Bentley was “the mini best man” when the MTV personality wed longtime love Taylor McKinney in Greenville, Florida, on October 8, she told Us Weekly exclusively.

He escorted his flower girl sister, Jayde, 16 months, down the aisle while pulling little brother Maverick, 4 months, behind in a red wagon. Bookout shares her two younger children with McKinney.

The reality personality wore a strapless couture gown as the couple married in front of 165 guests, including Teen Mom OG costar Catelynn Lowell, at the intimate, rustic ceremony, which was officiated by her pastor grandfather.

Bentley’s father is Bookout’s ex-fiancé, Ryan Edwards. The little boy was born when she first appeared on MTV’s debut season of 16 and Pregnant in 2009.

Teen Mom OG airs Mondays on MTV at 9 p.m. ET.

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