The 42-year-old mom-of-three "fully believes this isn't just a honeymoon phase, but that Travis is the man she's going to share her dreams with," the friend reveals to OK!.
As for the rocker, "he's been telling everyone he's hit the jackpot with Kourtney," spills the pal, adding that Barker, 45, who has two kids of his own, has already started shopping for rings.
"He's planning an ultra-romantic proposal," the pal adds, pointing out that the musician, who recently surprised Kardashian with an over-the-top flower arrangement and plane banner birthday message, is big on grand gestures. "He's still looking for the perfect ring, but that doesn't mean the baby-making has to wait until it's on her finger."
Speaking of grand gestures, Barker got Kardashian's name tattooed on his chest, so it definitely seems the two are in it for the long haul. As OK! previously reported, he was spotted out earlier this month on April 9 with "Kourtney" inked on his bod.
The two have been spending plenty of time together. Most recently, they were on a PDA-packed romantic getaway in Utah — and posted some steamy pictures to prove it. While the recent snaps on Instagram got a lot of love from their fans, Kardashian's ex Younes Bendjima seemed to shade the couple for their TMI-IG pics.
"Shamelessness has become so normal in today's society that modesty has become strange," Bendjima wrote on a since-deleted Instagram Story.
The pair were suspected to be an item in January when they were spotted in Palm Springs, Calif., together, but have been friends for several years now. "Travis has been in the Kardashians' inner circle for many years now, and he's always had a soft spot for Kourtney — and vice versa," an insider previously told OK! about what took them so long to start dating.
It seems their relationship was worth the wait. We'll be on bump watch!