Sharing a series of photos of the little girl, Aljaz gushed: "Guess who's turning two today? Aaaa. Melting... [heart emoji] Happy birthday little Zala."
Followers of the pro dancer were quick to message, with fellow Strictly star Nadiya Bychkova writing: "Happy birthday Zala!" One fan remarked: "Wow she’s just a mini version of your sister! Happy birthday."
WATCH Janette talk about future baby plans with husband Aljaz
Ever since Aljaz first became an uncle to little Zala in October 2018, the 30-year-old regularly shares photos of his niece and gushes about her on social media. The young tot is the first child of the Slovenian dancer's sister Lara.
In July, Aljaz - who is married to fellow pro Janette Manrara - revealed that Zala is set to become a big sister. "The sunniest day just got better," Aljaz announced. "My little Zala is going to be a big sister. Which means... I am going to be an UNCLE again! GEEEET INNNN [sic]."
Aljaz shared these adorable photos of his niece Zala
Aljaz has previously spoken to HELLO! about his bond with Zala and his desire to become a dad, saying: "She's beautiful, a little angel. I'm obsessed with kids… If someone had told me five years ago that my little sister was going to have a baby before me, I wouldn't have believed them. But I feel everything comes at the right time when it's supposed to come."
Aljaz's wife Janette is also keen on having a family sometime in the future. Whilst speaking to good friend Gorka Marquez on an Instagram live back in May, she jokingly admitted that she and Aljaz were going to have a baby.
"Aljaz and I are going to have a baby and move to Manchester," she told the Strictly dancer, before telling him that they could then raise their children together. "That's it. Done," she added.
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