diff --git a/test/test_pitytree.cc b/test/test_pitytree.cc
index d0b03dc..4dd496b 100644
--- a/test/test_pitytree.cc
+++ b/test/test_pitytree.cc
@@ -1,62 +1,144 @@
 #include "../src/PityTree.hh"
 #include "../src/PityTest.hh"
-//#include "../../../src/utils.hh"
+#include "../../../src/std_utils.hh"
+#include "../../../src/utils.hh"
 #include <iostream>
 #include <exception>
+using namespace pEp;
 using namespace pEp::PityTest11;
 
-class Node : public PityTree<Node> {
+// -----------------------------------------------------------------------------------------------
+
+class AbstractNode : public PityTree<AbstractNode> {
 public:
-    Node() = delete;
-    Node(const std::string &name);
-    Node(const std::string &name, Node &parent);
+    // Constructors
+    AbstractNode() = delete;
+    explicit AbstractNode(const std::string &name);
+    explicit AbstractNode(const std::string &name, AbstractNode &parent);
+    AbstractNode(const AbstractNode &rhs, AbstractNode &self);
+
+    // methods
+    virtual int implMe(int magic_nr) = 0;
+    AbstractNode *clone() override = 0;
 
+    // fields
     std::string color;
-    int age;
+    int age{};
 };
 
-Node::Node(const std::string &name) : PityTree<Node>(*this, name) {}
+AbstractNode::AbstractNode(const std::string &name) : PityTree<AbstractNode>(*this, name) {}
 
-Node::Node(const std::string &name, Node &parent) : PityTree<Node>(*this, name, parent) {}
+AbstractNode::AbstractNode(const std::string &name, AbstractNode &parent) :
+    PityTree<AbstractNode>(*this, name, parent)
+{
+}
 
-std::string readKey()
+AbstractNode::AbstractNode(const AbstractNode &rhs, AbstractNode &self) :
+    PityTree<AbstractNode>(rhs, self)
 {
-    std::string ret;
-    std::cin >> ret;
-    return ret;
+    color = rhs.color;
+    age = rhs.age;
 }
 
-void not_throwing(){
-    throw std::runtime_error{"Fsd"};
+
+// -----------------------------------------------------------------------------------------------
+
+class ANode : public AbstractNode {
+public:
+    explicit ANode(const std::string &name);
+    explicit ANode(const std::string &name, AbstractNode &parent);
+    ANode(const ANode &rhs);
+    ANode *clone() override;
+    int implMe(int magic_nr) override;
+};
+
+ANode::ANode(const std::string &name) : AbstractNode(name) {}
+ANode::ANode(const std::string &name, AbstractNode &parent) : AbstractNode(name, parent) {}
+ANode::ANode(const ANode &rhs) : AbstractNode(rhs, *this) {}
+
+int ANode::implMe(int magic_nr)
+{
+    return 23;
 }
 
-void throwing(){
-    throw std::runtime_error{"Fsd"};
+ANode *ANode::clone()
+{
+    return new ANode(*this);
+}
+
+// -----------------------------------------------------------------------------------------------
+
+class BNode : public AbstractNode {
+public:
+    explicit BNode(const std::string &name);
+    explicit BNode(const std::string &name, AbstractNode &parent);
+    BNode(const BNode &rhs);
+    BNode *clone() override;
+    int implMe(int magic_nr) override;
+};
+
+BNode::BNode(const std::string &name) : AbstractNode(name) {}
+BNode::BNode(const std::string &name, AbstractNode &parent) : AbstractNode(name, parent) {}
+BNode::BNode(const BNode &rhs) : AbstractNode(rhs, *this) {}
+
+int BNode::implMe(int magic_nr)
+{
+    return 42;
+}
+
+BNode *BNode::clone()
+{
+    return new BNode(*this);
+}
+
+// -----------------------------------------------------------------------------------------------
+
+void not_throwing()
+{
+    throw std::runtime_error{ "Fsd" };
+}
+
+void throwing()
+{
+    throw std::runtime_error{ "Fsd" };
 }
 
 int main(int argc, char *argv[])
 {
-    Node a{ "a" };
+    // Create lone node
+    ANode a{ "a" };
     std::cout << a.getPath() << std::endl;
-    PITYASSERT(a.isRoot() == true, "");
-    PITYASSERT(a.getName() == "a","");
-    PITYASSERT(&(a.getRoot()) == &a,"");
-    PITYASSERT(a.getParent() == nullptr,"");
-    PITYASSERT(a.getChildren().size() == 0,"");
+    PITYASSERT(a.isRoot() == true, "a");
+    PITYASSERT(a.getName() == "a", "b");
+    PITYASSERT(&(a.getRoot()) == &a, "c");
+    PITYASSERT(a.getParent() == nullptr, "d");
+    PITYASSERT(a.getChildRefs().size() == 0, "e");
 
-    Node b{ "b", a };
+    // Create node here, and make it a child of another node
+    BNode b{ "b", a };
     std::cout << b.getPath() << std::endl;
-    PITYASSERT(a.isRoot() == true,"");
-    PITYASSERT(&(a.getRoot()) == &a,"");
-    PITYASSERT(a.getParent() == nullptr,"");
-    PITYASSERT(a.getChildren().size() == 1,"");
-    PITYASSERT(&b == &(a.getChild("b")),"");
-    PITYASSERT_THROWS(a.getChild("invalid"),"");
-
-    PITYASSERT(b.isRoot() == false,"");
-    PITYASSERT(&(b.getRoot()) == &a,"");
-    PITYASSERT(b.getParent() == &a,"");
-    PITYASSERT(b.getChildren().size() == 0,"");
+    PITYASSERT(a.isRoot() == true, "f");
+    PITYASSERT(&(a.getRoot()) == &a, "g");
+    PITYASSERT(a.getParent() == nullptr, "1");
+    PITYASSERT(a.getChildRefs().size() == 1, "2");
+
+    PITYASSERT(&b == &(a.getChild("b")), "3");
+    PITYASSERT_THROWS(a.getChild("invalid"), "4");
+    PITYASSERT(b.isRoot() == false, "5");
+    PITYASSERT(&(b.getRoot()) == &a, "6");
+    PITYASSERT(b.getParent() == &a, "7");
+    PITYASSERT(b.getChildRefs().size() == 0, "8");
+
+    // Create a copy of the node in the parent node
+    b.addCopy(ANode("c")).addCopy(ANode("d"));
+    std::cout << a.to_string() << std::endl;
+
+    b.addCopy(BNode("c1")).addCopy(BNode("e"));
+    std::cout << a.to_string() << std::endl;
+
+    b.getChild("c1").getChild("e").addCopy(ANode(a), "a1");
+    std::cout << a.to_string() << std::endl;
 
+    a.getChild("b").addCopy(ANode(a), a.getName() + "1");
     std::cout << a.to_string() << std::endl;
 }