Hi all

Let me explain my problem in the simpliest way i can.
I have 2 excel sheet like:

First sheet:

Andrea YES
Steve YES
John

Second sheet:
On the second sheet these names can be found multiple times (for example 'John' as well)
and if I put a YES in sheet 1 after 'John' then I would need Excel to put YES to every John's in sheet 2 automatically.

Can I do it with formulas or a script?