class Parent
  include Mongoid::Document

  embeds_many :children, cascade_callbacks: true

  # uncommenting this is a work around to get the callbacks to fire
  # before_destroy :destroy_children

  # private
  # def destroy_children
  #   children.each(&:destroy)
  # end
end

class Child
  include Mongoid::Document

  before_destroy lambda { puts "before destroy" } # never fires
  after_destroy lambda { puts "after destroy" } # never fires
end