diff --git a/app/controllers/quantities_controller.rb b/app/controllers/quantities_controller.rb
index 043b9de..944ac4b 100644
--- a/app/controllers/quantities_controller.rb
+++ b/app/controllers/quantities_controller.rb
@@ -3,7 +3,8 @@ class QuantitiesController < ApplicationController
 
   before_action :init_session_filters
   before_action :find_project_by_project_id, only: [:index, :new, :create, :filter, :parents]
-  before_action :find_quantity, only: [:edit, :update, :destroy, :move]
+  before_action :find_quantity, only: [:edit, :update, :destroy, :move,
+                                       :new_child, :create_child]
   before_action :authorize
 
   def index
@@ -75,6 +76,24 @@ class QuantitiesController < ApplicationController
     render :index
   end
 
+  def new_child
+    @parent_quantity = @quantity
+    @quantity = @project.quantities.new
+    @quantity.domain = @parent_quantity.domain
+    @quantity.parent = @parent_quantity
+    @quantity.build_formula
+  end
+
+  def create_child
+    @quantity = @project.quantities.new(quantity_params)
+    if @quantity.save
+      flash[:notice] = 'Created new quantity'
+      prepare_quantities
+    else
+      render :new_child
+    end
+  end
+
   private
 
   def init_session_filters
diff --git a/app/views/quantities/_index.html.erb b/app/views/quantities/_index.html.erb
index 3d509d1..b63cfd6 100644
--- a/app/views/quantities/_index.html.erb
+++ b/app/views/quantities/_index.html.erb
@@ -46,6 +46,10 @@
           <td class="description"><%= q.description %></td>
           <td class="formula"><%= checked_image q.formula %></td>
           <td class="action unwrappable">
+            <%= link_to l(:button_child), new_child_quantity_path(q), {
+              remote: true,
+              class: "icon icon-add"
+            } %>
             <%= link_to l(:button_edit), edit_quantity_path(q), {
               remote: true,
               class: "icon icon-edit"
diff --git a/app/views/quantities/_new_child_form.html.erb b/app/views/quantities/_new_child_form.html.erb
new file mode 100644
index 0000000..b78077f
--- /dev/null
+++ b/app/views/quantities/_new_child_form.html.erb
@@ -0,0 +1,15 @@
+<%= labelled_form_for @quantity,
+  url: create_child_quantity_path(@parent_quantity),
+  remote: true,
+  html: {id: 'new-child-form', name: 'new-child-form'} do |f| %>
+
+  <%= render partial: 'quantities/form', locals: {f: f} %>
+
+  <div class="tabular">
+    <p>
+      <%= submit_tag l(:button_create) %>
+      <%= link_to l(:button_cancel), "#",
+        onclick: '$(this).closest("tr").remove(); return false;' %>
+    </p>
+  </div>
+<% end %>
diff --git a/app/views/quantities/create_child.js.erb b/app/views/quantities/create_child.js.erb
new file mode 100644
index 0000000..dd4e21b
--- /dev/null
+++ b/app/views/quantities/create_child.js.erb
@@ -0,0 +1,2 @@
+<%= render partial: 'body_trackers/flash' %>
+$('#quantities').html('<%= j render partial: 'quantities/index' %>');
diff --git a/app/views/quantities/new_child.js.erb b/app/views/quantities/new_child.js.erb
new file mode 100644
index 0000000..1272e4c
--- /dev/null
+++ b/app/views/quantities/new_child.js.erb
@@ -0,0 +1,8 @@
+<%= render partial: 'body_trackers/flash' %>
+$('tr[id=quantity-<%= @parent_quantity.id %>]').nextUntil('tr.quantity').remove();
+var columns = $('table > thead > tr > th').length;
+$('tr[id=quantity-<%= @parent_quantity.id %>]').nextAll('tr.quantity').first().before(
+  '<tr><td class="form" colspan="'+columns+'">' +
+  '<div id="new-child-quantity"><%= j render partial: "quantities/new_child_form" %></div>' +
+  '</td></tr>'
+);
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 795d2d0..6db430e 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -17,6 +17,7 @@ en:
   field_code: 'Formula'
   field_shortname: 'Short name'
   button_retake: 'Retake'
+  button_child: 'Child'
   activerecord:
     errors:
       models:
diff --git a/config/routes.rb b/config/routes.rb
index 9702467..22ca0f1 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -27,6 +27,8 @@ resources :projects, shallow: true do
       resources :sources, only: [:index, :create, :destroy]
       resources :quantities, only: [:index, :new, :create, :edit, :update, :destroy] do
         member do
+          get 'new_child'
+          post 'create_child'
           post 'move/:direction', to: 'quantities#move', as: :move
         end
         collection do
diff --git a/init.rb b/init.rb
index 419aaef..40478f0 100644
--- a/init.rb
+++ b/init.rb
@@ -28,7 +28,7 @@ Redmine::Plugin.register :body_tracking do
       ingredients: [:new, :create, :edit, :update, :destroy, :toggle, :toggle_column,
                     :import],
       sources: [:create, :destroy],
-      quantities: [:new, :create, :edit, :update, :destroy, :move],
+      quantities: [:new, :create, :edit, :update, :destroy, :move, :new_child, :create_child],
       units: [:create, :destroy],
     }, require: :loggedin
   end