One year after tying the knot with Travis Barker, Kourtney Kardashian remains on cloud nine and is celebrating the milestone.

April 5 marks a significant day for Kourtney Kardashian, as she reminisced on Instagram, “One year ago today, an Elvis impersonator married me and Travis Barker after the Grammys and way too much tequila in a chapel in Las Vegas!” The 43-year-old reality star added, “One of the best nights of our lives, dreaming of a lifetime filled with fun adventures together.”

Despite her younger sisters Kim and Khloé Kardashian's combined four divorces, Kourtney remains confident in her marriage with Travis, 47. An insider shared, “She knows it will last because, unlike with her siblings’ marriages, she was friends with Travis forever before she tied the knot with him. Kourtney says that’s their ‘secret sauce.’”

Embracing Married Life Kourtney's confidence in her marriage led her and Travis to agree to an April 13 Hulu special, Til Death Do Us Part, documenting their three ceremonies – the unofficial Las Vegas vows, a courthouse event in Santa Barbara, and a glamorous wedding in Portofino, Italy. Kourtney explained, “This is our personal archive footage that we are sharing with the world.”

However, her famous family members believe this decision was ill-advised. “Kourtney’s sisters told her that airing her wedding on TV is the kiss of death. It was for their marriages,” says the insider. “Khloé, who really believes in jinxes, especially thinks so, while Kim just worries Kourtney will be haunted by the special if she and Travis ever did break up.”

Despite her sisters' concerns, Kourtney remains unshaken. “Kourt is actually offended that her sisters doubt the long-term success of her marriage,” says the insider. “In response, she’s taken shots at their past relationships, telling Kim and Khloé things like, ‘My marriage will work because I actually love him, not just the idea of him!’”

As it stands, Kourtney is enjoying married life. “Kourt didn’t think she’d love married life this much since she’s always resisted it,” notes the source, pointing out that she had dated the father of her three children, Scott Disick, on and off for nine years but rejected several proposals. “One year in, and Kourtney’s relationship with Travis is better than ever – so she’s tuning out all the noise.”