--- a/net/minecraft/world/level/block/InfestedBlock.java
+++ b/net/minecraft/world/level/block/InfestedBlock.java
@@ -52,7 +_,7 @@
         Silverfish silverfish = EntityType.SILVERFISH.create(level, EntitySpawnReason.TRIGGERED);
         if (silverfish != null) {
             silverfish.snapTo(pos.getX() + 0.5, pos.getY(), pos.getZ() + 0.5, 0.0F, 0.0F);
-            level.addFreshEntity(silverfish);
+            level.addFreshEntity(silverfish, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SILVERFISH_BLOCK); // CraftBukkit - add SpawnReason
             silverfish.spawnAnim();
         }
     }
