diff --git a/poincare/include/poincare/addition.h b/poincare/include/poincare/addition.h
index 0d2ddac4c..7039f59d2 100644
--- a/poincare/include/poincare/addition.h
+++ b/poincare/include/poincare/addition.h
@@ -10,7 +10,8 @@ class Addition : public Expression {
     ExpressionLayout * createLayout(ExpressionLayout * parent) override;
     float approximate(Context& context) override;
   private:
-    Expression * m_children[2];
+    Expression * m_left;
+    Expression * m_right;
 };
 
 #endif
diff --git a/poincare/src/addition.cpp b/poincare/src/addition.cpp
index 596af7be0..60781950a 100644
--- a/poincare/src/addition.cpp
+++ b/poincare/src/addition.cpp
@@ -2,19 +2,19 @@
 #include "layout/horizontal_layout.h"
 
 Addition::Addition(Expression * first_operand, Expression * second_operand) {
-  m_children[0] = first_operand;
-  m_children[1] = second_operand;
+  m_left = first_operand;
+  m_right = second_operand;
 }
 
 Addition::~Addition() {
-  delete m_children[1];
-  delete m_children[0];
+  delete m_left;
+  delete m_right;
 }
 
 float Addition::approximate(Context& context) {
-  return m_children[0]->approximate(context) + m_children[1]->approximate(context);
+  return m_left->approximate(context) + m_right->approximate(context);
 }
 
 ExpressionLayout * Addition::createLayout(ExpressionLayout * parent) {
-  return new HorizontalLayout(parent, m_children[0], '+', m_children[1]);
+  return new HorizontalLayout(parent, m_left, '+', m_right);
 }