diff --git a/src/app/ui/timeline/timeline.cpp b/src/app/ui/timeline/timeline.cpp
index f60b9172c..a9b267f3a 100644
--- a/src/app/ui/timeline/timeline.cpp
+++ b/src/app/ui/timeline/timeline.cpp
@@ -168,21 +168,6 @@ SelectLayerBoundariesOp get_select_layer_in_canvas_op(ui::Message* msg)
     return SelectLayerBoundariesOp::REPLACE;
 }
 
-bool get_layer_index(LayerGroup* parent, const Layer* layer, layer_t& index)
-{
-  for (Layer* child : parent->layers()) {
-    if (child->isGroup() && get_layer_index(static_cast<LayerGroup*>(child), layer, index)) {
-      return index;
-    }
-
-    if (child == layer) {
-      return true;
-    }
-    index++;
-  }
-  return false;
-}
-
 } // anonymous namespace
 
 Timeline::Hit::Hit(int part, layer_t layer, col_t frame, ObjectId tag, int band)
@@ -4070,12 +4055,6 @@ layer_t Timeline::getLayerIndex(const Layer* layer) const
   return -1;
 }
 
-layer_t Timeline::getLayerIndexFromSprite(const Layer* layer) const
-{
-  layer_t index = 0;
-  return get_layer_index(m_sprite->root(), layer, index) ? index : -1;
-}
-
 bool Timeline::isLayerActive(const layer_t layerIndex) const
 {
   Layer* layer = getLayer(layerIndex);
@@ -4597,7 +4576,7 @@ void Timeline::onDrop(ui::DragEvent& e)
 
   // Determine at which frame and layer the content was dropped on.
   frame_t frame = m_frame;
-  layer_t layerIndex = getLayerIndexFromSprite(m_layer);
+  layer_t layerIndex = m_sprite->root()->getLayerIndex(m_layer);
   InsertionPoint insert = InsertionPoint::BeforeLayer;
   DroppedOn droppedOn = DroppedOn::Unspecified;
   TRACE("m_dropRange.type() %d\n", m_dropRange.type());
diff --git a/src/app/ui/timeline/timeline.h b/src/app/ui/timeline/timeline.h
index 0c80ac765..3793ed0dd 100644
--- a/src/app/ui/timeline/timeline.h
+++ b/src/app/ui/timeline/timeline.h
@@ -355,8 +355,6 @@ private:
   gfx::Point getMaxScrollablePos() const;
   doc::Layer* getLayer(int layerIndex) const;
   layer_t getLayerIndex(const Layer* layer) const;
-  // Get layer index regardless of visibility in the UI.
-  layer_t getLayerIndexFromSprite(const Layer* layer) const;
   bool isLayerActive(const layer_t layerIdx) const;
   bool isFrameActive(const col_t frame) const;
   bool isCelActive(const layer_t layerIdx, const col_t frame) const;
diff --git a/src/doc/layer.cpp b/src/doc/layer.cpp
index a4f72a1e1..b7f77ea6c 100644
--- a/src/doc/layer.cpp
+++ b/src/doc/layer.cpp
@@ -597,4 +597,22 @@ void LayerGroup::displaceFrames(frame_t fromThis, frame_t delta)
     layer->displaceFrames(fromThis, delta);
 }
 
+layer_t LayerGroup::getLayerIndex(const Layer* layer, layer_t& index) const
+{
+  for (Layer* child : this->layers()) {
+    if ((child->isGroup() && static_cast<LayerGroup*>(child)->getLayerIndex(layer, index) != -1) ||
+        (child == layer)) {
+      return index;
+    }
+    index++;
+  }
+  return -1;
+}
+
+layer_t LayerGroup::getLayerIndex(const Layer* layer) const
+{
+  layer_t index = 0;
+  return this->getLayerIndex(layer, index);
+}
+
 } // namespace doc
diff --git a/src/doc/layer.h b/src/doc/layer.h
index 665a8ce52..0ede0371d 100644
--- a/src/doc/layer.h
+++ b/src/doc/layer.h
@@ -236,9 +236,13 @@ public:
 
   bool isBrowsable() const override { return isGroup() && isExpanded() && !m_layers.empty(); }
 
+  layer_t getLayerIndex(const Layer* layer) const;
+
 private:
   void destroyAllLayers();
 
+  layer_t getLayerIndex(const Layer* layer, layer_t& index) const;
+
   LayerList m_layers;
 };