Last year, Sam admitted on her radio show, Nova’s Kate, Tim and Marty, that he remembered vivid details about the smooch, which occurred when they were both only 15.
“Can I be creepy?” Sam asked, before confessing: “I remember how she tasted 20 years ago.”
Describing the kiss, he said Kate tasted “like peaches” and “strawberries and cream” with the Summer Bay star responding that was “the nicest thing anybody has ever said to me in this studio.”
Sam added: “You tasted like a lolly and you were so nice to me, thank you - because I was terrified - so thank you for looking after me.”
Things weren’t always so rosy in Samuel’s dating life however.
In 2006, Sam’s former girlfriend Lainie Woodlands took her own life just hours after he broke up with her, a death he described as his life’s “biggest sadness”.
“The love of my life hanged herself,” he said on Anh Do’s Brush With Fame a decade later. “And, I'm still very upset for her and for her family.
“I'd definitely say it's probably my life's biggest sadness. And in a way, the more time goes by, the more it hurts.”
Samuel, who also lost his mother to suicide as a child, shared that it was difficult for him to let go of his grief over the loss.
“You know how they reckon that you come to terms with your grief as you go along? Not with this one,” he added. “With every year it gets more profound. My sadness grows.”
When host Anh Do asked Sam whether losing so many people close to him made him question whether life was unfair, the actor remained positive.
“I’m not a victim. I don’t know if I’m just bullsh--ting myself, but I see my time with Lainie as a gift,” he explained.
“Maybe I lost her earlier than I would have liked but I had some of her. I got to share my life with her.”
Understandably, following the death of Lainie, Samuel didn’t appear to rush into a new relationship and stayed single for around 13 years before finding happiness with a new love.
In 2019, rumours swirled that Karl Stefanovic’s ex-wife Cassandra Thorburn and Sam had been flirting up a storm behind the scenes when they both took part on Network Ten’s Dancing With The Stars.
“When you're feeling vulnerable, it's nice if someone finds you attractive,” he told Who when quizzed on the romance rumours. “In another life, who knows what would have happened?”
WATCH: WHO's Rapid Fire Questions with Samuel Johnson (Story continues after video)
But it appears another woman may have caught his eye, Emma Rooke, who was also friends with Sam’s late sister Connie.
"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 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," shared one DWTS staffer at the time.
"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."
If you’re struggling and need someone to talk to, contact Lifeline (lifeline.org.au) on 1311 14 or visit Headspace at (headspace.org.au). Visit Beyond Blue at (beyondblue.org.au) or call 1300 22 4636. You can also contact the Kids Help Line on 1800 55 1800.
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