Rags Martel reported on the FA's search for living descendants of the founding fathers of the sport earlier this year.
The search has been successful and has unearthed London born descendants as well as people from as far afield as America and New Zealand.
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"I think there are a number of things I didn't do correctly in this case", said Ademola Dada.
Mr Johnson vowed to lie down in front of the bulldozers when he was elected MP for the west London constituency of Uxbridge & South Ruislip
The course is designed to help spot the signs of suspicious behaviour.