TV personality Kourtney Kardashian attends Escape to Total Rewards at Hollywood & Highland Center on March 1, 2012 in Hollywood, California. Credit: Michael Buckner/Getty Images

Happy Birthday Kourtney Kardashian!

Though she's got plenty to celebrate--the reality star turned 33 Wednesday, and is expecting her second child with love Scott Disick--Mason's mama is skipping the big birthday bash, and opting for a low-key day instead.

"Kourtney and the fam just got back from Mexico," a source close to Kardashian tells Us Weekly. "Best trip ever! So that's it for [her birthday plans]."

Due later this summer, the pal says Kardashian is focused on resting and relaxing as she and Disick prep to welcome the newest addition to the Kardashian crew.

"They were at Joe Francis' house [in Mexico], just a big group of friends," the Kardashian pal shares. "Relaxing, a real vacation."

The vacay held extra-special significance for the Kourtney and Kim Take New York star: says the insider, "[This was the] last vacation before baby number two!"

Kardashian hasn't been shy about showing off her growing baby bump; in March, she escaped to the Dominican Republic with her family, where she flaunted her pregnancy curves in a sexy, tie-dyed two-piece.

"She's a little bigger this time [than she was with Mason]," Kourtney's younger sis, Kim told Us. "But she still looks amazing!"