Vanessa Minnillo & Nick Lachey Celebrate in Mexico

Fresh off the heels of engagement news, Vanessa Minnillo and Nick Lachey have jetted off to Mexico to celebrate their relationship milestone.

Ironically, not only do the newly engaged share an adoration for each other, but they also share the same birthday, which this Tuesday.

"They are [in Mexico] to celebrate their engagement and their upcoming birthdays," a source tells PEOPLE. "They are having a great time together and enjoying their special moment."

Minnillo, pictured holding a balloon that shows she is turning the big 3-0, is also sporting her new ring. Lachey will turn 37.