We are planning our daughter's wedding on short notice (10 weeks) and I am unsure of how to handle this situation. The groom really doesn't have any close friends (and no time to become close enough to acquaintenances for them to be included in a wedding) and does not want to include his 2 step brothers in the wedding (the family is not close at all). Also, his father is not living. The groom really wants his four year old son to be his best man, and he would like to include our younger daughter's boyfriend as a groomsman, as he has gotten to know him fairly well. Our daughter has her best friend as her matron of honor and wants her two sisters and one more friend to stand up with her. How do we handle this properly? (The wedding will be rather small and on a very tight budget.)
Since this isn't quite traditional with such a young boy as the best man (he is way too young), it would be best for this to very informal. And yet, even with the informality, your daughter would have too many attendants. She could just have her one MOH. The others could assist in other ways.
But, with the informal wedding there are few rules as there are few expectations. So, just plan with an eye on how guests will perceive it. Plus, have someone close ready to scoop the little one up if he becomes anxious. Young children are unpredictable.