Sir Mo Farah ran his way to four Olympic gold medals while carrying the weight of a shocking secret on his back. Farah, 42, will be swapping the running track for the hallowed Old Trafford turf to play for at Soccer Aid.

His Three Lions shirt will carry the name 'Farah', which will always be synonymous and the two more he won . Yet, in the shocking the legendary long-distance runner Mo Farah was not his real name.

In the documentary, he told the world that his birth name was Hussein Abdi Kahin and the name he was known by, Mohamed Farah, actually belonged to another person. Born in Somaliland, Farah's father was killed by a piece of shrapnel from a bazooka blast, when the athlete was only four years old.

For his safety, Farah was sent to neighbouring Djibouti, before he was eventually illegally trafficked into the United Kingdom. An unidentified woman, posing as his mother, brought him to the UK under the guise of staying with family.

He was given the name Mo Farah - who was a different child - and fake documents with the name and his picture. He was told to use this identification to enter the country. Farah was only nine years old.

Upon arrival, he realised what had happened when he saw a worried father searching for his child, whose place Farah had taken. The woman he stayed with destroyed the paper containing his family's contact details and forced him to care for another family's children, threatening that he would never see his own family again if he spoke out.

In the documentary, Farah said: "If I wanted food in my mouth, my job was to look after those kids, shower them, cook for them, clean for them. She said, 'If you ever wanna see your family again, don't say anything.' Often I would just lock myself in the bathroom and cry."

At 11, Farah started at Feltham Community College, where staff were told he was a Somali refugee. His form tutor, Sarah Rennie, described him as "unkempt and uncared for" and "emotionally and culturally alienated," due to his limited English.

However, during PE lessons, teachers discovered his exceptional athletic talent. Alan Watkinson, Farah's PE teacher, said: "The only language he seemed to understand was the language of PE and sport."

Watkinson contacted social services, which led to Farah being fostered by another Somali family. With Watkinson's help, Farah gained British citizenship under the name Mohamed Farah in 2000.

From that moment, Farah's life and career took a dramatic turn, leading him to become a four-time Olympic gold medallist and a six-time world champion. Farah was forced to leave his mother Aisha and two brothers behind in Somaliland, where they live on a farm.

While studying at a university in west London, Farah met his future wife Tania Nell. The couple now have four children together: Rhianna, Hussein Mo, Amani and Aisha Farah.

In a remarkable twist, the documentary also features a video call between Farah and the real Mohamed Farah. However, according to , the athlete had to sever ties with him and change his phone number after he was allegedly harassed for money by the man and about ten others who had obtained his number.