Hi Tarik,
Greetings from Syncfusion support.
From your query we can understand that you want to provide the data for child grid through ajax each time while expanding the row.
we would like to inform you that load event of the Grid will trigger only for initial rendering. While using Hierarchy grid the child grid will be rendered only once while expanding the row for the first time. After that the expanded row will not re-render the child grid each time while expanding and collapse. This is the default behavior.
So before proceeding your query, could you please share the code example for grid and child grid. Your code example will be helpful for us to validate further about your requirement.
Regards,
Manivel
