The lovebirds celebrated together on Wednesday, with Bindi, 21, sharing two adorable photos of the fiancés in their holiday sweaters.
“All smiles because I’m in love with you, it’s Christmas and my sweater lights up…” she captioned the photos.
She also posted a photo of herself building a gingerbread house in a red Christmas sweater that reads, “Instead of gifts I’m giving everyone my opinion.”
“Christmas sweater or New Years resolution?” she joked.
Bindi and Powell, 23, announced their engagement on July 24, Irwin’s 21st birthday, after dating for nearly six years.
The couple is set wed next year at the Australia Zoo, where the Irwin family lives and works. It’s also the place the young conservationist met Powell, a wakeboarder from Florida, in 2013 while he was visiting the zoo.
Speaking to PEOPLE in October, the Animal Planet star said she was finding special ways to honor her late father Steve Irwin at the upcoming wedding. (The beloved wildlife expert died in 2006 after being attacked by a stingray off the coast of northern Australia.)
“I really want to include Dad on the day and make sure that he is with us in some way — just little bits of Dad that will make it feel like he’s there with us,” Bindi said. “We’ll have candle lighting ceremony, so we’ll be able to all get up as a little family and light a candle in his honor and share a few words on what an amazing dad he was and still is.”