It is known that in poor countries if someone becomes rich, all his relatives and extended family rely on him to support them at least to some extent, and most of the times he does support them. Do you think this is the case also with Kenyan runners or Ethiopians who became rich?
I know Farah was requested financial help by his brothers and probably denied them
https://www.mirror.co.uk/news/uk-news/mo-farahs-brothers-rift-olympic-5750458