Every Photo from Katharine McPhee and David Foster's Hawaiian Vacation with the Whole Family

A Romantic Getaway

Aloha! Katharine McPhee and fiance David Foster are living their best life on a vacation to Lanai, Hawaii. Foster, 69, and McPhee, 34, got engaged during the summer of 2018, and have been traveling around the island together, going snorkeling, driving around in a vintage blue car and soaking up the tropical sun.

Living on Island Time

In a selfie snapped by Foster, McPhee sticks out her tongue next to her husband-to-be, who is sporting a festive tropical shirt. "Island life," he captioned the photo.

“We genuinely love and respect each other and have for a very long time,” McPhee told PEOPLE in September. The pair, who have a 34-year age difference, first met in 2006 when Foster mentored her and other contestants on Season 5 of American Idol.

A Post-Christmas Vacation

Two days after Christmas, McPhee posted a photo of herself sporting a yellow bikini and a flower in her hair, "mele kalikimaka is hawaii’s way..." she captioned the shot, referring to the way to say "Merry Christmas" in Hawaiian. Foster's daughter Erin, 36, teased her soon-to-be step mom in the comments of the photo, writing "Grandma!!!! Wtf I don’t want to be next to you at the pool."

Driving in Style

To kick off the new year, McPhee shared a photo of herself posing in a blue car while wearing a black high-waisted two-piece swimsuit. "riding into 2019," she wrote.

Cabana Life

McPhee channeled her inner Kardashian as she posed for a photo inside of a cabana. The Waitress star's mom Peisha joined the couple on their trip, and was responsible for taking this sexy snapshot. "if you listen closely, you can actually hear my mom whispering “you’re doing amazing sweetie!” McPhee wrote, referring to Kris Jenner's iconic complement.

Lounging In Style

During thier vacation, McPhee and Foster, as well as McPhee's mom and sister, Adriana, stayed at the luxurious Four Seasons Resort in Lanai.

Spreading Peace

McPhee stood by a lounge chair with the ocean as her backdrop as she threw up a peace sign in another vacation snap.

Sibling Bonding

McPhee and her sister prepped for their snorkeling adventure by sporting flippers and masks before diving into the Pacific. "My little Mermaids!!," Peisha wrote beside the photo. "Getting ready for our snorkeling trip!"

A Boating Adventure

During the excursion, the former American Idol contestant wore flippers before hopping in the water to go snorkeling. "I’m coming for you Ariel," she captioned a boomerang of herself kicking her legs on the boat.

A Musical Element

Of course, McPhee couldn't resist performing a little during their getaway, so she took the stage to sing a rendition of "That's Life" from her show Smash. "Happy New Year!! What entertainment we had !!" her mom captioned a video of McPhee singing.

Girls' Night

McPhee and her family enjoyed dinner at the resort while wearing tropical dresses and leis. "Am I not the luckiest and most blessed Mama to have these two beautiful daughters!" Peisha wrote, followed by the hashtags #happiness and #joyful.

Family Affair

Foster posed with his soon-to-be in-laws for a quick photo during a traditional Hawaiian luau. "AMAZING time in Lanai," Peisha wrote of the snap.

McPhee and Foster's relationship began “on a friend basis” she told PEOPLE. But it later transformed into a romance that took them both by surprise. “There are just a lot of things when you look at the history of our relationship, neither of us could have written it. I would never have imagined that this would be our future together,” she says.

Selfie Time

The women stopped for a selfie ahead of the luau, with Peisha writing, "Heaven in Lanai with my girls !"

Family-Friendly Teasing

Foster's daughters, Sara, 37, and Erin, 36, also joined in on the family fun, and Sara posted a cheeky photo with her soon-to-be stepmom. "When your mom refuses to dress age appropriately," she joked in the caption.

Matching Suits

Sara also shared a sweet image of her daughter, Josephine Lena, 3, wearing goggles and a swimsuit that matched hers. "Who wore it better?" she wrote.

Sandy Toes

Erin spent some time on the sand in Lanai, and posted a photo of herself sporting a black bikini with the caption: "Thought I’d end the year showing a different side of me."

Date Night

Erin's beau Simon Tikhman also joined the vacation. During their date night on New Year's Eve, Erin joked that he made a "list of resolutions and then gave them to me so I can improve for 2019. But I explained to him that’s not how it works."