How adorable are these young lovebirds?
“For 20 years you have brought endless amounts of light into this world. I am thankful every day to have you in my life,” her post began. “We’ve travelled the world together and had some of the most extraordinary adventures. I’m so excited to continue on this beautiful journey with you.”
“Your kindness and strength is inspiring, and your smile will always be my favorite,” Irwin, 18, continued. “Happy birthday my sunshine, you’re amazing.”
The birthday boy also took to social media to share a few posts about celebrating his special day with the Dancing with the Stars champion.
“20 years old will definitely be the most difficult age for me to get used to thus far…,” he wrote on Instagram. “I couldn’t have asked for a better way to spend it than living in the middle of nowhere for a few days with my girl @bindisueirwin, she sure knows how to give me an amazing birthday.”
Powell also added a cute video of the pair enjoying the Supermoon under the Australian stars.
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Irwin and her boyfriend, a professional wakeboarder who is currently a college student in Florida, first met in November 2013 while he was visiting the Australia zoo. After the pair began a long-distance relationship, Irwin told PEOPLE that the two rely on Skype and FaceTime to keep in touch while they’re apart.