The Thames was nothing compared to what Philip has done – he is a true hero, my hero
When David Walliams last visited Kenya for Sport Relief in 2011 he was inspired to undertake his epic Thames swim by a destitute orphan called Philip.
That September, in just eight days, he swam 140 miles along the river.
Along the way he raised more than £1million.
Here is his own account of his reunion with the 13-year-old and how the boy's life has been transformed.
"Even though it was little under a year since I met him for the first time I felt nervous about going back to Kenya to see Philip again.
I wanted to witness first-hand how Sport Relief cash had helped him and I wanted my wife Lara to meet the boy who'd helped me through the darkest moments of my Thames swim, but I couldn't help but be apprehensive about what I'd find.
Philip was very much a little boy when I first met him last year, younger in appearance than his 12 years would suggest, but already having experienced profound tragedy and loneliness.
When I first saw him he slept under a plastic sheet in the intersection of a busy dual carriageway together with a small group of friends.
By day this band of brothers begged for food or picked up scraps left on plates by restaurant diners and at night they huddled together, praying that they would avoid the physical and even sexual abuse that they were so vulnerable to.
The chain of events which led to Phillip finding himself in such a wretched situation started five years ago. Until that point life had been relatively good — his wasn't from a wealthy family but he had parents who loved him and were there for him and as a bright boy his future was secure.
His life soon changed though after his father suddenly became very ill and was hospitalized. On the way to visit him in hospital Philip's mother was hit by a car and from nowhere and within a matter of weeks both Phillip's parents were dead and this eight-year-old boy found himself one of the 20,000 street children living rough in Kisumu, Kenya's third largest city.
For four bleak years Philip and his friends fought to survive — and then their luck finally changed when a worker from the Sport Relief-funded Hope For Victoria Children (HOVIC) project spotted them.
HOVIC provides a raft of basic but essential care for street kids starting with food, shelter and medical care — and crucially also offers these youngsters the chance to escape the poverty trap they find themselves in through education.
Since I saw him last, Philip has been given that chance and I hoped he had grasped it with both hands, but after so long on the streets the transition back to school was going to be an incredibly tough one.
I needn't have worried.
When I arrive I'm immediately struck by how much he's grown, which in large part is thanks to the nutritious diet he now gets rather than being forced to exist on scraps.
His English vocabulary has also grown as much as he has and he chats away with an endearing mixture of shyness and self-assurance.
The other boys are all there too. This little group who used to eke an existence under a sheet in the middle of the dual carriageway are all here, standing in front of me in their school uniforms!
The difference from 12 months ago couldn't be starker.
I'd forgotten how softly spoken Philip was but there's no mistaking that he has the air about him of a boy who has an inner determination not to be beaten by what life has thrown at him.
He still wants to be a pilot, a dream that seemed tragically out of reach when I saw him last — but now, with the drive he possess, with the hurdles he has already overcome, you wouldn't bet against him making it happen.
He tells me that the science he studies will help him fly the planes, the geography for map work and the English for talking to the control tower.
As with many of the poorest children here in Kenya and across Africa Philip knows the value and importance of education in a way that most youngsters back home don't — when he talks about his teachers he mentions the wisdom they give him. He is acutely aware what school and education means, it's his escape route.
And as he showed me around his school it becomes clear just how proud he is of it.
It's basic of course — concrete floors and sparse classrooms but, it is a safe environment, one which he says his parents would have been happy to see him in and he is determined to soak up every piece of knowledge he can while he is there.
He is somehow more earnest, serious, focused, than when I met him before. He knows he has been given a huge chance and he intends to take it.
The following day we went back to the spot where Philip used to sleep, as busy, as congested and as dangerous as ever. There at the top of the tree the boys' huddled under were the filthy ropes they used to secure their plastic sheet with — a reminder just how far they had come, just how much change Sport Relief and everyone who supported it has made happen.
The fact that my swim played a part in that makes me very proud indeed, but in terms of facing up to a challenge, the Thames was nothing compared to what Philip has done — he is a true hero, my hero."
Tune into Sport Relief: The Final Score on BBC One at 11.25pm on Sunday.
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