Race Across The World contestant James broke down in tears during an emotional scene, which viewers have called "the most moving TV moment of the year".
On Wednesday's instalment of the BBC One show, James became tearful after his sister Betty opened up about her health battle, which has left her "without a womb".
Betty, 25, spoke about her condition, known as MRKH (Mayer-Rokitansky-Küster-Hauser Syndrome) a rare congenital disorder that affects the female reproductive system. She told viewers that she discovered that she did not have a uterus, womb and only has one kidney, at age 16.
Betty and James, 21, who were not that close before appearing on the show together, has seen theuir relationship get stronger throughout their journey across Eastern Asia.
Opening up about her condition, Betty told James: "My frustrations and down moments come periodically, I want to be resilient and brave and whatever, but my condition I do believe has made me have this mindset of being negative and not really liking the person I am.
"It means that I don't have a uterus, I don't have a womb and I only have one kidney as well.
"I think as a young woman, you're told you're going to marry, you're going to have a family, and from a young age when that's taken away from you, it does put doubts in your mind. Doubts in your purpose as a person, I suppose,” she added.
"It's okay, you know, honestly, I forget that you can't have children," James said, to which his sister replied: "Me and you have never even had a conversation about it have we?
“It's definitely made me develop, I think, a lot of the negative attributes that I have like overthinking and wanting to feel in control, because I just feel like at 16 something was taken away from me that I couldn't control.
"So, when you've been saying "everything happens for a reason," I can't believe that."
Later speaking to the camera, James said: "To hear that was tough. It was the first time we've talked about it, and I have heard it from Betty herself and it's only now that I realise how much it does affect her and, excuse me, there's a frog in my throat."
Unable to fight back the tears, he said: "Brave is now probably an understatement, I'll have to think of a new word for her." He then said: "Can someone just come and hug me please?"
Viewers took to X to share how touched they were by the episode.
One wrote: "Omg Betty and James each week make me love them even more, as if I was their parent. Bizarre to say I know. They are fun, the loveliest, kindest, strongest siblings. Emotionally there for each other... I hope they win this."
Another added: "This will be the most moving TV moment of the year I feel." A third commented: "How brave of Betty to tell everyone about her health. Oh and James asking the cameraman for a hug."
While a fourth commented: "Can someone just come and hug me please [crying emojis] James and Betty are my winners."
The brother and sister duo are among the group competing for a £20,000 prize. They have become fan favourites and reached the penultimate leg of the race, travelling from Bukittinggi to Jakarta.
They had a tricky bus journey before arriving in Muara Enim in South Sumatra, where they faced more trials, including accidentally leaving their travel documents on the bus and a burst tyre on their taxi.
"We've not showered, we've not eaten, we're hot and sweaty," Jamed complained. "Everything is just adding up... It's not been for me this whole Sumatra leg. Maybe because it's outside our control it sometimes gets a little bit more frustrating. I just feel like I'm mentally not properly in it anymore."
Betty explained: "I could feel James getting really frustrated today… The tables have definitely turned in that aspect because usually, it's me moaning and him being like 'live in the moment and find a positive!'"
The final episode of Race Across the World will air on Wednesday 29 May at 9pm on BBC One.
