diff --git a/.gitmodules b/.gitmodules
index 294504b3..e69de29b 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +0,0 @@
-[submodule "samples/advanced/QuickQanava"]
-	path = samples/advanced/QuickQanava
-	url = git@github.com:cneben/QuickQanava.git
diff --git a/samples/advanced/QuickQanava b/samples/advanced/QuickQanava
deleted file mode 160000
index 0264f6ad..00000000
--- a/samples/advanced/QuickQanava
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 0264f6adae314c5eca5293e9e9974465b3fae23f
diff --git a/src/qanGraph.cpp b/src/qanGraph.cpp
index 2cb8933a..843c751d 100644
--- a/src/qanGraph.cpp
+++ b/src/qanGraph.cpp
@@ -2021,8 +2021,8 @@ std::vector<const qan::Node*>   Graph::collectAncestors(const qan::Node& node) c
 {
     // ALGORITHM:
       // 0. Collect node neighbour.
-      // 1. Collect ancestors of neighbours.
-      // 2. Remove original neighbour from ancestors.
+      // 1. Collect ancestors of neighbors.
+      // 2. Remove original neighbors from ancestors.
 
     const auto collectAncestorsDfs_rec = [](const qan::Node* visited,
             std::vector<const qan::Node*>& parents,
diff --git a/src/qanGroup.cpp b/src/qanGroup.cpp
index ceb7b68b..85278964 100644
--- a/src/qanGroup.cpp
+++ b/src/qanGroup.cpp
@@ -60,7 +60,7 @@ const qan::Graph*   Group::getGraph() const noexcept { return qan::Node::get_gra
 
 std::unordered_set<qan::Edge*>  Group::collectAdjacentEdges() const
 {
-    std::unordered_set<qan::Edge*> edges = collectAdjacentEdges0();
+    std::unordered_set<qan::Edge*> edges = qan::Node::collectAdjacentEdges();
     if (is_group()) {
         for (const auto groupNode: qAsConst(group_nodes())) {
             if (groupNode != nullptr) {
@@ -72,7 +72,7 @@ std::unordered_set<qan::Edge*>  Group::collectAdjacentEdges() const
                 } else {
                     auto qanNode = qobject_cast<qan::Node*>(groupNode);
                     if (qanNode != nullptr) {
-                        auto nodeEdges = qanNode->collectAdjacentEdges0();
+                        auto nodeEdges = qanNode->collectAdjacentEdges();
                         edges.insert(nodeEdges.begin(), nodeEdges.end());
                     }
                 }
diff --git a/src/qanGroup.h b/src/qanGroup.h
index 7f31077a..50bae795 100644
--- a/src/qanGroup.h
+++ b/src/qanGroup.h
@@ -84,7 +84,7 @@ class Group : public qan::Node
     /*! \brief Collect this group adjacent edges (ie adjacent edges of group and group nodes).
      *
      */
-    std::unordered_set<qan::Edge*>  collectAdjacentEdges() const;
+    virtual std::unordered_set<qan::Edge*>  collectAdjacentEdges() const override;
 
 public:
     friend class qan::GroupItem;
diff --git a/src/qanNode.cpp b/src/qanNode.cpp
index 17211377..a7057539 100644
--- a/src/qanNode.cpp
+++ b/src/qanNode.cpp
@@ -137,7 +137,7 @@ QAbstractItemModel* Node::qmlGetOutEdges() const
     return super_t::get_out_edges().model();
 }
 
-std::unordered_set<qan::Edge*>  Node::collectAdjacentEdges0() const
+std::unordered_set<qan::Edge*>  Node::collectAdjacentEdges() const
 {
     std::unordered_set<qan::Edge*> edges;
     for (const auto in_edge: qAsConst(get_in_edges())) {
diff --git a/src/qanNode.h b/src/qanNode.h
index 7456f63e..f59f5f3b 100644
--- a/src/qanNode.h
+++ b/src/qanNode.h
@@ -151,7 +151,7 @@ class Node : public gtpo::node<QObject,
 
 public:
     //! Get this node level 0 adjacent edges (ie sum of node in edges and out edges).
-    std::unordered_set<qan::Edge*>  collectAdjacentEdges0() const;
+    virtual std::unordered_set<qan::Edge*>  collectAdjacentEdges() const;
     //@}
     //-------------------------------------------------------------------------
 
diff --git a/src/qanNodeItem.cpp b/src/qanNodeItem.cpp
index 68b51f54..cd179dd4 100644
--- a/src/qanNodeItem.cpp
+++ b/src/qanNodeItem.cpp
@@ -161,10 +161,15 @@ void    NodeItem::collapseAncestors(bool collapsed)
     // 1.
     const auto ancestors = graph->collectAncestors(*node);
 
+    qWarning() << "-- ANCESTORS: ";
+    for (const auto ancestor: ancestors)
+        qWarning() << ancestor->getLabel();
+    qWarning() << "------------";
+
     // 2.
     std::unordered_set<qan::Edge*> ancestorsEdges;
     for (const auto ancestor: ancestors) {
-        const auto edges = ancestor->collectAdjacentEdges0();
+        const auto edges = ancestor->collectAdjacentEdges();
         std::copy(edges.begin(), edges.end(), std::inserter(ancestorsEdges, ancestorsEdges.end()));
     }
 
@@ -198,7 +203,7 @@ void    NodeItem::collapseChilds(bool collapsed)
     // 2.
     std::unordered_set<qan::Edge*> childsEdges;
     for (const auto child: childs) {
-        const auto edges = child->collectAdjacentEdges0();
+        const auto edges = child->collectAdjacentEdges();
         std::copy(edges.begin(), edges.end(),
                   std::inserter(childsEdges, childsEdges.end()));
     }