Ian Poulter may not have celebrated a victory on the course for several years, but he just celebrated one of his biggest off it — 18 years of marriage to his longtime love, Katie Poulter. The Ryder Cup veteran turned LIV Golf star marked the milestone with a sentimental Instagram post, and judging by the flood of reactions from fans, fellow pros, and legends alike, the golf world was all in.

“18 Years happy is the best feeling in the World,” Poulter wrote in a heartfelt post alongside throwback photos from their 2007 wedding at Woburn Abbey. “Our journey has been many more and very special. Creating 4 beautiful kids and a life I couldn’t have ever dreamed of. Let’s rock this second half ❤️👍🏼😘🥰,” the caption continued.

The post was quickly filled with love from all corners of the sport. LPGA legend Annika Sorenstam chimed in with a simple but elegant “Congratulations,” while fellow Ryder Cup veteran Paul Azinger gave a hearty “Happy anniversary 👏.” Comments poured in from golf circles and fans as they joined in to celebrate the milestone of a man who’s been part of some of golf’s most iconic moments.

Katie Poulter has been a constant in Ian Poulter’s life since 1995, when the two first met, back when she was working as a nurse and he was just beginning to find his footing in golf. After 12 years of dating, they tied the knot in a stunning ceremony at Woburn Abbey in Bedfordshire. The wedding infamously clashed with the Seve Trophy, to which Poulter cheekily remarked, “I’ve kept Katie waiting for ten years, so I had better not say I can’t make it on the day we’ve agreed because a golf tournament has come up.”

Now based in Florida’s Lake Nona Golf & Country Club, where they rub shoulders with the likes of Justin Rose, Graeme McDowell, and Sergio Garcia, the couple also maintains a home near Milton Keynes in the UK. They have four children together —Aimee-Leigh, Luke, Joshua, and Lily-Mai, with Luke already carving his own path in professional golf.

Through it all—career highs, transatlantic moves, and raising four kids—Ian and Katie’s bond has remained rock solid. While Poulter’s flair and fire have made him one of Europe’s most recognizable golfing personalities, it’s Katie’s quiet strength and unwavering support that’s helped keep things going behind the scenes. Whether walking the fairways during his Ryder Cup appearances or holding down the fort at home, she’s always been by his side.

And, like any great long-term relationship, theirs comes with a few legendary stories, none more memorable (or hilarious) than the mystery of the Arnold Palmer-signed $100 bill.

Ian Poulter recalls his wife accidentally spending Arnold Palmer’s signed $100 bill

Katie, in a funny story told by Poulter, once managed to spend a $100 bill that was signed by none other than Arnold Palmer. Long before Arnold Palmer passed away in 2016, he and Ian Poulter had become friendly—a relationship Poulter cherished deeply. So much so that at one point, Poulter asked the golf legend to autograph a $100 bill, planning to frame it alongside a similarly signed note from Jack Nicklaus. The idea? A one-of-a-kind piece of golfing memorabilia, sealed and protected forever.

But that’s not how it actually went down. In a 2017 media interview, Poulter recounted the hilarious misstep that followed. “He signed a $100 bill, which my wife actually spent one time,” Poulter laughed. “It was in the safe. She didn’t realize it was actually signed by Arnie, so it’s out there somewhere. I have no idea what she did with it. Not a clue. It was probably in Publix, to be honest. She probably went to get some groceries,” he added.

The mix-up only came to light when Poulter finally got around to framing the bills. “Shock horror when I actually did go in there to put it in the frame,” he said. “You can imagine what I said, ‘Where has the [$100] bill gone?’ She says, ‘I don’t know. I must have spent it.'”

In true Poulter fashion, he handled it with a grin and even called in a favor to get a replacement. “I phoned up and I said, ‘I’m really sorry, but is there any chance I could pop in and get Arnie to sign another hundred?'” he recalled the hilarious moment.  So somewhere out there, in the hands of a lucky cashier or buried in a grocery store deposit, might just be the most valuable $100 ever spent.