I found the following answer in Reporting Forum:
But I don't know how to check the data count within SubReport1_NeedDataSource
We are using a SQLdatasource.
Thanks...
Kelly
https://www.telerik.com/forums/how-to-hide-subreports-if-they-do-not-have-the-data-needed-to-be-display#s7pqNThtmkS75q1uwVoqrg
Private Sub SubReport1_NeedDataSource(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SubReport1.NeedDataSource
Dim subReport As Telerik.Reporting.Processing.SubReport
subReport = CType(sender, Telerik.Reporting.Processing.SubReport)
If (...no data expression...) Then
subReport.Visible = False
End If
End Sub