The 19-year-old wakeboarder was competing in England prior to his trip to Australia for his lady love’s milestone birthday.
Powell honored his girlfriend on Instagram, posting a sweet photo with the caption: “Happy birthday to the most amazing person I know. I'm amazed by everything you have already achieved and I can't even begin to imagine everything you'll accomplish from this point on. I'm very blessed to have you as such a huge part of my life and I'm beyond thankful you've let me be a part of yours. I hope today is as amazing as you are.”
And though the couple seems smitten with one another, don’t expect them to be heading down the aisle anytime soon.
"I don't think I'm at a point in my life where marriage and getting engaged is really a huge priority right now for me. Maybe in five years, but right now I'm really happy with where I'm at," Irwin recently told ET. "I'm really happy with our relationship and I think we'll just continue to have fun. It's just nice to have someone there no matter what."