His two eldest boys, Lennox and Nate, grapple with autism, while his youngest daughter, Madeline, was diagnosed with cystic fibrosis shortly after being born – just six weeks before Luke left for Survivor.
"If I win $500,000 it would be life-changing for my family. It'll give my kids a future that I want to give them so that's why I'm doing it,” Luke said during his time on the show.
Despite being knocked out in fourth place, fans quickly cooked up a GoFundMe campaign in the hopes to raise the equivalent sum of the Survivor first prize to help Luke look after his three kids.
So determined fans were to lend a helping hand to the Perth-based star that the numbers kept climbing until eventually surpassing the $500,000 goal - the excess of which Luke and his wife kindly donated to charity.
WATCH: Survivor's Luke Toki thanks fans for donating to GoFundMe
Now in the vastly different reality TV world of Big Brother VIP, Luke has never forgotten the kindness of the Australian public in helping out his beautiful family.
Speaking candidly to Big Brother in Tuesday's episode, the King of the Jungle became emotional as he discussed the massive support from the Australian public in the weeks following his second Survivor appearance.
"When I played the second time I left a sick daughter at home and it was the most gut-wrenching thing in the world, but I wanted to win the money to support my family," Luke told Big Brother in the Diary Room.
Luke continued, "Big Brother, I've come from nothing - I've worked pretty much my whole life and I risked everything to become the King of the Jungle.
"I tried my hardest, and even though I lost again the Australian public were amazing to me and gifted me the money."
"It's hard talking about it," Luke said as he became visibly emotional, adding, "I hate talking myself up."
Big Brother asked, "Do you not believe what the Australian public see?" to which Luke replied, "I don't know - I just try my hardest and just try to win."