Runner Mark is going the extra mile in tribute to his tragic sister

The 31-year-old will be taking part in the London Marathon on Sunday to raise funds for the YoungMinds charity which helps teenagers to deal with issues such as bullying and depression.

His sister Chelsea Clark, who was a pupil at Wolverhampton Girls High School, died suddenly at home in June 2011.

An inquest is expected to be held later this year.

Thirteen people benefited from organ donations from the teenager. Their mother, 57-year-old Mrs Margaret Clark, said at the family's home in Finchfield Lane, Finchfield: "She was good at sorting out the problems of other people.

"She was so caring and supportive. She did not just carry one donor card. She had one stuck to her bedroom wall above the light switch so that everybody could see it."

Mr Foster, who lives in Essington Way, Willenhall, said: "The reason I have chosen the YoungMinds charity as the beneficiary is simple. Chelsea suffered from depression, and YoungMinds is precisely the kind of charity she could have turned to. The family miss her every day. She was irreplaceable and meant the world to all of us.

"She was so bubbly and friendly, and we really miss her lovely laugh. She was beautiful both inside and outside."

Mr Foster added: "I took up running after her death because it helped me to focus on different things and took my mind off what had happened. Raising money for charity is my way of dealing with the loss.

"All the family have been helping with fundraising, and we have collectively collected £5,000. We have set a target of £10,000 but I will not stop when we reach that. I will continue to do this for the rest of my life."

Other fundraising events organised by members of the family include a supermarket bag pack that raised £630, cake sales, car boot sales and a recording of a song written as a tribute to Chelsea which had a limited run of records offered for sale.

Mother-of-nine Mrs Clark said: "Chelsea was a very bright student who was in Year 8 at the time of her death.

"She was extremely gifted with science and creative things like arts and crafts. She wanted to be a vet. After she died, we found some booklets from YoungMinds at a counselling centre.

"Now the ambition of the family is to raise enough money to ensure that these booklets are available in every sick bay, doctors surgery, youth club and school in the country. If the life of one teenager can be saved as a result of this, then Chelsea will not have died in vain."

Those wishing to contribute to the charity can do so through the website www.justgiving.com/chelsea-gillian-courtney-clark