recommendation letter

hello everybody,
I need to write a letter of recommendation for a security guard that works in the building where I live;
his boss is unfare with him so I would like to write a letter to his manager where I say good things about him that is such a nice person and has 4 kids;
I am not mother language plus I am not really good in writing so I am asking for your help;
I thank you all in advance,
god bless you