Upvote:2
It is better if an application stacks up by itself without the need for a covering letter - there is space in the application to provide further information, try to utilise just this if you can. If you really feel a cover letter is essential, I would a) limit it to max 1 page; b) use bullet points; c) focus on clarifying the previous refusal reasons. You could use a cover letter to explain your uncleβs situation, however, in my opinion, without evidence to show he can provide the promised accommodation and food your application is very likely to be refused. Taking into account that Nigeria is considered a high risk country by the U.K. if I were you I would postpone my application until I could meet the criteria in my own right.