diff --git a/poincare/src/simplify/rules_generation/node.cpp b/poincare/src/simplify/rules_generation/node.cpp
index d0b5869f3..76f64d5c5 100644
--- a/poincare/src/simplify/rules_generation/node.cpp
+++ b/poincare/src/simplify/rules_generation/node.cpp
@@ -9,6 +9,9 @@ Node::Node(std::string * name, std::vector<Node *> * children) :
   if (children == nullptr) {
     m_children = new std::vector<Node *>();
   }
+  for (Node * child : *m_children) {
+    child->m_parent = this;
+  }
 }
 
 Node::~Node() {
diff --git a/poincare/src/simplify/rules_generation/node.h b/poincare/src/simplify/rules_generation/node.h
index 2ecbe4e9f..fb2a689bb 100644
--- a/poincare/src/simplify/rules_generation/node.h
+++ b/poincare/src/simplify/rules_generation/node.h
@@ -15,9 +15,9 @@ public:
   int flatIndexOfChildNamed(std::string name);
 protected:
   virtual void generateFields(Rule * context, std::string &indentation) = 0;
-protected:
   std::string * m_name;
   std::vector<Node *> * m_children;
+  Node * m_parent;
 };
 
 #endif
diff --git a/poincare/src/simplify/rules_generation/selector.cpp b/poincare/src/simplify/rules_generation/selector.cpp
index b9ec4a532..7fff9c532 100644
--- a/poincare/src/simplify/rules_generation/selector.cpp
+++ b/poincare/src/simplify/rules_generation/selector.cpp
@@ -9,12 +9,15 @@ Selector::Selector(Type type, std::string * name, std::vector<Selector *> * chil
 }
 
 void Selector::generateFields(Rule * context, std::string &indentation) {
+  Selector * parent = (Selector *)m_parent;
   switch (m_type) {
     case Type::Variable:
       std::cout << indentation << ".m_match = ExpressionSelector::Match::Any," << std::endl;
       break;
     case Type::Wildcard:
       std::cout << indentation << ".m_match = ExpressionSelector::Match::Wildcard," << std::endl;
+      // Wildcard should always be the last element of a parent
+      assert(parent->m_children->back() == this);
       break;
     case Type::ExpressionType:
       std::cout << indentation << ".m_match = ExpressionSelector::Match::TypeAndValue," << std::endl;