如何从rails上的索引视图中的一对多关系表中获取上次更新日期

class Parent < ApplicationRecord
  has_many :children
end

class Child < ApplicationRecord
  belongs_to :parent
end

class ParentsController < ApplicationController
  def index
    @parents = Parent.includes(:children).all
  end
end

<% @parents.each do |parent| %>
  <h2><%= parent.name %></h2>
  <p>Last updated: <%= parent.updated_at %></p>
  
  <h3>Children:</h3>
  <% parent.children.each do |child| %>
    <p><%= child.name %></p>
  <% end %>
<% end %>