The 21-year-old from Brisbane became separated from friends during the attack on London Bridge and the nearby Borough Market late on Saturday night.
Family, friends and her former Moreton Bay College school community were notified this afternoon that Zelenak, who had been working in London as an au pair, was among the dead.
Her aunt, Tara, said the young woman’s mother Julie Wallace broke down when she learnt the news during her travels to the UK.
“Even though there was limbo for days, there was still a bit of hope,” she said via Facebook.
“We are all so distraught to have lost our little Sara.
“She is the most beautiful, happy, positive young lady with so much to live for.
“Her heart and spirit will live on in all of us.”
Close friend Sam Hetherington said Zelenak had brought “so much joy” into her life and said she couldn’t believe they wouldn’t be able to grow old together.
“Just Thursday I messaged you and you told me everything will always work out,” she wrote on Facebook.
In a statement, Moreton Bay College also expressed “deep sadness” at news of the popular former student’s passing.
“This is the first time our college community has been touched by an act of terrorism and our hearts are broken by the loss of Sara,” a statement said.
“Sara was a positive, popular student who always had a smile on her face. She embodied the values of Moreton Bay College and was adored by her peers and staff.
“This is how she will be forever remembered.”
An online fundraiser that had notched up its target of $15,000 for her family also confirmed her death and reopened the drive in a bid to continue to provide support.
It follows confirmation South Australian woman Kirsty Boden, 28, who had been working as a nurse in London, also died in the attack.
Four Australians were caught up in the van and knife attack which left seven innocent people dead and 48 injured before the three terrorists were shot dead by police.
Two other Australians were confirmed injured but are recovering well.
Prior to confirmation of her daughter’s death, Zelenak’s mother told Brisbane radio station 97.3FM she and her husband had been looking forward to travelling to the UK to see their daughter.
“The last time I spoke to her was our time Friday afternoon at 4:42 and she said, ‘Oh mum! It’s only 28 days until you and I and dad can have baguettes and cheese and croissants in Paris. I’m so excited to go to Paris!'”
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