David Tennant: My Sport Relief Sierra Leone diary

He has lived there for 17 years now with his wife Kadiatu, his 18-month-old daughter Fatmata and his six-year-old son Ibrahim, and struggles every day to sell enough rubbish to provide for his family. He shares with me his pain at not being able to give his family a better life and his guilt at not being able to earn enough to send his son to school, which would one day allow him to provide a better life for his family.

We had planned to film in their home but the thick, noxious fumes made it impossible and unsafe. I watched him and his family disappear through that smoke, feeling utterly helpless and brokenhearted for the dad who just wants, like me and every other father, to do the best for his family.

Next I met Alusine (12) and Mohamed (10), two brothers who work on the dump, “picking”. They work from morning to night sifting through burning rubbish to try to find anything they can sell on to make enough money to survive.

On a good day they can make 1,000–2,000 leones – about 15–30p. With both their parents dead, they live next to the dump with their grandmother, who is too frail to work.

Without the project funded by Sport Relief, kids like this would have a bleak future. But with the money raised by you, kids like Alusine and Mohammed could one day soon go to the YMCA Kissy Primary School, which costs just £50 a year.

Day Two – Ola During Children’s Hospital, Freetown

This is the only place where children can get specialised treatment in Sierra Leone. I was shown all the wonderful changes that have taken place thanks to all you brilliant people who have ever put your hand in your pocket.

A project called Welbodi, funded by Sport Relief, provides trained nurses who can make diagnoses without a doctor present. There is now a lab on site so the process of diagnosing is made faster and more efficient, and the introduction of an x-ray machine and its operators has been revolutionary. Daily vaccination clinics are now held to try and prevent the children getting sick in the first place.

All of these things are funded in some way by Sport Relief. Not only that, but the project also works within communities to educate and encourage families to get healthcare earlier to give them a better chance of recovery.

It was such an uplifting experience to see what an enormous difference all that money we ask of you does. It changes the lives of so many people and I truly believe that you have helped people live who otherwise wouldn’t have. You have given a future to children who previously only had survival, and given people hope when they hadnone.

If you have ever wondered if giving to Sport Relief really changes anything, here is the proof that is does. Things are better here because of you.

Day Three – Isatu's home, Freetown

My final visit was to the home of an extraordinary woman named Isatu. Early last year she found a 13-year-old boy called Saidu crying near her village. The tears were for his mother, Sento, who was very ill with an HIV-related illness.

He took Isatu to his mother and she decided that she had to help. She moved them both into her home so she could care for these strangers herself. What makes this already astonishing act of selflessness even more extraordinary is that not only did she and her family not have much money but she too is living with HIV.

For the past five months the two families have lived together in two rooms in rural Freetown, where Isatu can help care for Sento and her son. Money is tight, and sometimes Sento doesn’t have enough food to take her medication, so must drink salt water to line her stomach.

Sento spends her days lying on a door that rests on the floor as there is no other furniture. On a good day she can walk a little with a stick in one hand and her son in the other, but is totally reliant on Isatu and Saidu to stay alive. As a volunteer carer she is funded by a project spon- sored by Sport Relief.

My time in Sierra Leone showed me the best and worst of humanity. Whether it’s a father trying his hardest to give his kids a better future, children smiling as they pick their way through burning rubbish or doctors and nurses dedicating their lives to trying to save others, even when they know they have come too late.

I know we go on at you to “pick up the phone” and “give what you can” but I’m asking again. Please know that you are so important and what you do is really quite miraculous.

Sport Relief is on tonight from 7:00pm on BBC1.

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