its perfectly normal t have spacing between teeth.....as d jaw is expanding and growing in size t accomodate permanent teeth,which r bigger in size dan milk teeth

Spaces between milk teeth in kids is normal. When milk teeth falls and permanent teeth erupts, these spaces helps in erupting them as they are bigger in size compare to their counterparts. The parents need to take good care of milk teeth and visit dentist with their kids every six months to 1 year so that any cavities are detected early and restored.

Gap between milk teeth are normal. It is in fact better because if there are no gaps the permanent teeth may show crowding later. The black spots could be decay ( early childhood varies) . Please get a dental check up