diff --git a/src/vs/workbench/parts/debug/common/debugModel.ts b/src/vs/workbench/parts/debug/common/debugModel.ts
index 5d16733beb80fb71640216554874e1c1e96436e2..ccb1ba5944621a81b3222db5b67a2670cf55f025 100644
--- a/src/vs/workbench/parts/debug/common/debugModel.ts
+++ b/src/vs/workbench/parts/debug/common/debugModel.ts
@@ -182,7 +182,7 @@ export abstract class ExpressionContainer implements debug.IExpressionContainer
 
 						const start = this.getChildrenInChunks ? this.startOfVariables : undefined;
 						const count = this.getChildrenInChunks ? this.indexedVariables : undefined;
-						return this.fetchVariables(start, count, 'indexed')
+						return this.fetchVariables(start, count, this.getChildrenInChunks ? 'indexed' : undefined)
 							.then(variables => childrenArray.concat(variables));
 					});
 			}