Hide Two Columns If One Is Blank

Currently using this code to search Column D and hide if the cells are blank. How would I go about also hiding Column C as well, If D is blank?

I am using the spreadsheet as a grading template. The assignment name is under column C and the grade under column D. If there is no grade then I would like to be able to hide the unused assignment column along with the empty grade column.

Sub HideColumnsInd()
With Application
.EnableEvents = False
.ScreenUpdating = False
End With
Dim rCell As Range
For Each rCell In Range("D3:D48")
If rCell = "" Then
rCell.EntireColumn.Hidden = True
Else
rCell.EntireColumn.Hidden = False
End If
Next rCell
Application.EnableEvents = True
End Sub