She has been quietly supporting heartbroken Samuel Johnson, even before he lost his sister Connie, and last week the popular actor couldn't help but share his joy after finding love with the "beautiful and gentle" woman who was by his and Connie's side throughout her inspirational cancer battles.
"This koala makes everything with me. We have built some unusual dreams together over many years," he captioned a photo of a brunette beauty, whose face was concealed but was later revealed to be Emma Rooke.
"Without her heart and brain, my dreams would remain just that. Thanks for building all the things with me little miss koala. I hope to build one more, as always, but as we know, it's not up to us."
Sam, 41, has been close to Emma for many years, but their bond appears to have become even stronger since Connie's death at just 40 years of age on September 8, 2017.
Emma was in the crowd at his performances for Dancing With The Stars, cheering him on as he won the dance competition and $50,000 for Love Your Sister, the charity he and Connie set up to support the Garvan Institute of Medical Research.
"His eyes lit up when he talked about his partner, but I think the two of them try and keep their relationship private," shares one DWTS staffer.
"I know Emma was at the finale to see Sam win and she was with him at the party afterwards. I think it's really sweet. If anyone deserves happiness, Sam does."
Emma had been best friends with Connie since the age of 12, when she had her first battle with cancer, with the pair meeting after Connie's final round of childhood chemotherapy treatment.
In an emotional Instagram post shortly before Connie's death, Sam told his followers that Emma was his sister's "bestie since, like, forever".
"She runs LYS top to bottom since Day 1. On her business card her title is quite rightly The Hectickest."
Last week, Emma all but confirmed the duo were dating after she captioned her post with what appeared to be a love letter from Sam.
"Her name is Emma and her heart is very almost too big. Thanks for being so thoughtful to so many Emma. One day I'm going to find the present for you that makes your heart sore no more. Just like you did for me."
It ends, "I love you always, from you know who".
Sam's happiness with Emma comes after years of heartache, including the loss of his long-time girlfriend, Lainie Woodlands, who committed suicide after they broke up in 2006.
Sam, who also lost his mum to suicide when he was a toddler, called Lainie the love of his life and admitted he fell into a depression after she died.
While he's dated others since then, including casting director Sarah Hallam, friends say it's Emma who has proved to be his rock and helped him move on from his past tragedies.
She was one of Sam's biggest supporters when he put his life and entertainment career on hold to cycle 15,995km across the country to raise millions for Love Your Sister in 2013, and has been quietly supporting him from the sidelines ever since.
WATCH: Sam speaks candidly about his last moments with his late sister Connie. Post continues below...
And last week Sam's loyal fans were quick to celebrate his new love. "Sweetheart now that's what I call romance," wrote one. "You both deserve happiness and I wish you all the best," penned another.
These days, Emma honours her best friend's legacy by helping Sam push Love Your Sister to meet its fundraising goals to vanquish cancer once and for all, but prefers to keep her romance private, spending time with Sam at his retreat at Daylesford, near Melbourne.