def remove_child(child)
      child = child.name if child.is_a?(Model)
      children.delete(child)
    end
def remove_child(child)
      child = child.name if child.is_a?(Model)
      children.delete(child)
    end
Deletes the specified child from children list

 @param child [Model,String,Symbol] the child to remove
 @return [Model] the deleted child, or nil if no matching component is
   found.