Chris Pratt and Katherine Schwarzenegger had some fun in the sun before ringing in the new year.

The couple was spotted enjoying a vacation together in Cabo San Lucas, Mexico on New Year’s Eve. Pratt, 39, went shirtless as he and Schwarzenegger, 29, lounged by the pool.

The author rocked a pink off-the-shoulder one-piece bathing suit as the Avengers: Infinity War star wore navy blue patterned swim shorts and a baseball cap.

Their romantic getaway comes just a month after the actor made their relationship Instagram official when he created a collage of his favorite photos of  Schwarzenegger in honor of her birthday.

“Happy Birthday Chief! Your smile lights up the room. I’ve cherished our time together,” the father of one captioned his Instagram post.

“Thrilled God put you in my life. Thankful for the laughs, kisses, talks, hikes, love and care,” Pratt concluded his sweet message.

RELATED VIDEO: Chris Pratt and Katherine Schwarzenegger Are Getting ‘Serious,’ Says Source: They’re ‘Hopeful for the Future’

Pratt and Schwarzenegger were introduced by Schwarzenegger’s mother, Maria Shriver (her dad is actor Arnold Schwarzenegger) in June and it wasn’t long before the pair was spotted on a date together that same month.

Since the summer, they have been spotted riding bikes, going on multiple church dates together and hanging out with each other’s families — including Pratt’s son Jack, 6, with ex Anna Faris.

“It’s only been a couple of months, but they’re both serious about the relationship and hopeful for the future,” a source close to the pair recently told PEOPLE. “Chris doesn’t just date to date, and neither does Katherine. She’s very excited. Family is very important to both of them, as well as their spirituality. She’s very, very sweet and maternal and great with his son.”


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Happy Birthday Chief! Your smile lights up the room. I’ve cherished our time together. Thrilled God put you in my life. Thankful for the laughs, kisses, talks, hikes, love and care.♥🍾🎉🎂

A post shared by chris pratt (@prattprattpratt) on Dec 13, 2018 at 5:32pm PST

//www.instagram.com/embed.js

RELATED: Chris Pratt & Katherine Schwarzenegger Enjoy Date with Her Dad: ‘Arnold Seemed Very Pleased with Him’

Pratt and Faris, 42, continue to amicably co-parent their son after they settled their divorce in November. Faris is dating cinematographer Michael Barrett.

The exes filed for divorce and requested joint custody of Jack in December 2017 and recently photographed together with their son as well as their significant others when they all celebrated Halloween together.

Read more: people.com