I believe this is what you want:

Private Sub Worksheet_Change(ByVal Target As Range)
Dim c As Range
Target.Interior.ColorIndex = 3
For Each c In Target.Dependents
c.Interior.ColorIndex = 3
Next c
End Sub

This is an event procedure, it fires whenever there is a change in a
cell manually. It examines which cells are dependent on the cell just
changed and highlights them as well.

To install and test:
In the sheet where you do your data changes, right-click on the sheet
tab and choose View Code.
In the VBA IDE paste the above code.

Is this what you need?

Kostis Vezerides