diff --git a/src/Umbraco.Web.UI.Client/libs/repository/repository-tree-data-source.interface.ts b/src/Umbraco.Web.UI.Client/libs/repository/repository-tree-data-source.interface.ts
index 7e484c86c2..aff4ec4451 100644
--- a/src/Umbraco.Web.UI.Client/libs/repository/repository-tree-data-source.interface.ts
+++ b/src/Umbraco.Web.UI.Client/libs/repository/repository-tree-data-source.interface.ts
@@ -3,5 +3,6 @@ import type { DataSourceResponse } from '@umbraco-cms/models';
 
 export interface RepositoryTreeDataSource {
 	getRootItems(): Promise<DataSourceResponse<PagedEntityTreeItemModel>>;
+	getChildrenOf(parentKey: string): Promise<DataSourceResponse<PagedEntityTreeItemModel>>;
 	getItems(key: Array<string>): Promise<DataSourceResponse<EntityTreeItemModel[]>>;
 }