diff --git a/.tool-versions b/.tool-versions
deleted file mode 100644
index f2a971aa75..0000000000
--- a/.tool-versions
+++ /dev/null
@@ -1 +0,0 @@
-ruby 3.2.2
diff --git a/app/views/qae_form/_matrix_question.html.slim b/app/views/qae_form/_matrix_question.html.slim
index 87df46c641..bfb0b96869 100644
--- a/app/views/qae_form/_matrix_question.html.slim
+++ b/app/views/qae_form/_matrix_question.html.slim
@@ -18,3 +18,8 @@ table.matrix-question-table.govuk-table class="#{'auto-totals-column' if questio
                 = "#{y_heading.label} numbers for #{x_heading.label}"
               input.js-trigger-autosave.matrix-question-input.govuk-input type="number" data-required-row-parent=question.required_row_parent min="0" step="1" name=question.input_name(suffix: "#{x_heading.key}_#{y_heading.key}") value=question.input_value(suffix: "#{x_heading.key}_#{y_heading.key}") id=question.input_name(suffix: "#{x_heading.key}_#{y_heading.key}") autocomplete="off" *possible_read_only_ops aria-describedby=(@form_answer.validator_errors && @form_answer.validator_errors[question.hash_key] ? "error_for_#{question.key}" : nil )
               span.govuk-error-message aria-live="polite"
+                - if @form_answer.validator_errors && @form_answer.validator_errors["#{question.hash_key}_#{x_heading.key}_#{y_heading.key}"].present?
+                  | Required
+                  span.govuk-visually-hidden id="error_for_#{question.key}"
+                    | Error:
+                  =< @form_answer.validator_errors[question.hash_key]
diff --git a/forms/award_years/v2024/social_mobility/social_mobility_step3.rb b/forms/award_years/v2024/social_mobility/social_mobility_step3.rb
index a005b46379..b10f860ca5 100644
--- a/forms/award_years/v2024/social_mobility/social_mobility_step3.rb
+++ b/forms/award_years/v2024/social_mobility/social_mobility_step3.rb
@@ -543,6 +543,7 @@ def mobility_step3
           classes "sub-question question-matrix"
           ref "C 5.2"
           required
+          required_rows :initiative_activities
           context %(
             <p>When answering this question, please refer to the guidance under C5.</p>
           )
diff --git a/forms/qae_form_builder/matrix_question.rb b/forms/qae_form_builder/matrix_question.rb
index d9b788fd37..0a5435b3fd 100644
--- a/forms/qae_form_builder/matrix_question.rb
+++ b/forms/qae_form_builder/matrix_question.rb
@@ -2,15 +2,16 @@ class QaeFormBuilder
   class MatrixQuestionValidator < QuestionValidator
     def errors
       result = super
-
       if question.required?
         question.y_headings.each do |y_heading|
           question.x_headings.each do |x_heading|
             suffix = "#{x_heading.key}_#{y_heading.key}"
 
-            if !question.input_value(suffix: suffix).present? && question.required_rows.include?(y_heading.key)
-              result[question.hash_key(suffix: suffix)] ||= ""
-              result[question.hash_key(suffix: suffix)] << "Required"
+            if !question.input_value(suffix: suffix).present?
+              if (question.required_row_parent && question.required_rows.include?(y_heading.key)) || !question.required_row_parent
+                result[question.hash_key(suffix: suffix)] ||= ""
+                result[question.hash_key(suffix: suffix)] << "Required"
+              end
             end
           end
         end