diff --git a/src/dr/evomodel/coalescent/smooth/SkyGlideLikelihood.java b/src/dr/evomodel/coalescent/smooth/SkyGlideLikelihood.java
index 95da6e244a..848a4bc56c 100644
--- a/src/dr/evomodel/coalescent/smooth/SkyGlideLikelihood.java
+++ b/src/dr/evomodel/coalescent/smooth/SkyGlideLikelihood.java
@@ -199,7 +199,6 @@ public double[] getDiagonalHessianLogDensityWrtLogPopSize() {
                     currentGridIndex = lastGridIndex;
                 }
             }
-            updateSingleTreePopulationInverseGradientWrtLogPopSize(index, diagonalHessian);
         }
 
         return diagonalHessian;