app port from old version

app/models/child.rb

@@ -0,0 +1,11 @@
+class Child < ActiveRecord::Base
+  has_many :parenthoods
+  has_many :parents, through: :parenthoods, source: :person
+
+  validates :first_name, presence: true
+  validates :last_name, presence: true
+
+  def name
+    "#{first_name} #{last_name}"
+  end
+end

app/models/parenthood.rb

@@ -0,0 +1,4 @@
+class Parenthood < ActiveRecord::Base
+  belongs_to :person
+  belongs_to :child
+end

app/models/person.rb

@@ -0,0 +1,25 @@
+class Person < ActiveRecord::Base
+  has_many :parenthoods
+  has_many :children, through: :parenthoods
+
+  validates :first_name, presence: true
+  validates :last_name, presence: true
+
+  scope :with_name, lambda { |name|
+    where("concat(first_name, ' ', last_name) RLIKE ?", name)
+  }
+
+  scope :just_parents, lambda {
+    joins(:children)
+      .order(:first_name)
+      .uniq
+  }
+
+  scope :staff, -> { where(staff: true) }
+
+  scope :admins, -> { where(admin: true) }
+
+  def name
+    "#{first_name} #{last_name}"
+  end
+end