Pregnant Kourtney Kardashian Shares Rare Glimpse at Son Mason with Brother Reign: 'Night Walk with My Boys'

Kourtney Kardashian Barker is enjoying quality time with her two sons before she adds another baby boy to the batch.

On Saturday, the Poosh founder, 44, spent some special time with Reign, 8, and Mason, 13, enjoying a walk at dusk with the boys after returning from her Hawaiian girl's trip with daughter Penelope and friends celebrating her 11th birthday.

"Night walk w my boys," she captioned the two photos. In one, you can see Reign posing with his blonde-streaked hair, a casual look completed with alien-printed Crocs, holding his hand to his chin pensively as he blurred past.

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In the second photo, the Lemme founder shared a rare glimpse at Mason, with the teen crossing the street wearing sweats with his shaggy haircut covering his eyes.

Earlier this month, the reality star and husband Travis Barker revealed the sex of their baby on the way in a sweet video shared on Instagram, where the expectant mom sits on Barker's lap behind his drumkit as he plays a drumroll.

Shortly after, Barker, 47, began a drumroll and he kissed his wife, before striking the drum's symbols just as a burst of blue streamers shot in the air behind them, confirming that the couple are having a boy.

The couple's upcoming arrival with also be Barker's fourth child. He is a dad to three children with ex Shanna Moakler: son Landon, 19, daughter Alabama, 17, and stepdaughter Atiana, 24.

After her pregnancy announcement earlier this month, a source shared with PEOPLE that Kardashian Barker "is just beyond excited."

"She had happy tears when she told her family. They have all known for a while," they shared. "Everyone is so happy for her. Kourtney can't wait to be a mom again. Her older kids are excited about the baby too."