Hi Nabia,
Thank you for your interest in Syncfusion Products.
Please refer the below code snippet which is used to set column header text for the ChildTable.
[C#]
DataTable childTable = GetChildTable();
childTable.Columns[0].Caption = "childTableID";
Please refer the sample from the below link, which illustrates this.
http://websamples.syncfusion.com/samples/Grid.Web/6.3.1.8/Grid_Web_Hierarchy/main.htmIn the abopve sample, the ChildTable has the column name as "childID" and it has been displayed as "childTableID".
Please let me know if this helps you.
Thanks,
Rekha