Kim, Kanye and their kids North and Saint enjoyed some time together during the island getaway, relaxing at a beachside house.
In just a few days, Kanye will turn 40, making the trip a double whammy celebration.
Kim recently took to her website to gush about hubby Kanye, writing, "Happy three-year anniversary babe! Thank you for being the best husband and father. I love you so much."
Meanwhile, Radar has learned exclusive details about the pair's high stakes vacation.
"Kim planned this entire trip without Kanye knowing and surprised him last minute," a source close to the 36-year-old mother of North, 3, and Saint West, 1, said. "She wanted to try and save their marriage."
West, who officially turns 40 on June 8, hadn't been spending much time with his family in the months leading up to the vacation.
After returning from a solo Wyoming trip, "Kim and Kanye have not had any time for themselves," the insider said.
As Radar previously reported, Kardashian has recently been caught in the middle of a nasty family feud, being forced to choose sides between her momager, Kris Jenner, 61, and her former stepfather Caitlyn, 67.
"With everything going on recently, Kim just wanted to get away without her entire family," the insider said. "She wanted it to just be her, Kanye and the kids."
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