Changing text to Bold from another cell entry

Hello

I'm trying to create an effect,..but it's not working out too easily.

I have 2 cells in a worksheet called Screening Form.
They are C22 and C23.

I would like it so that if "either" one has an entry...then cell AA24 reads "YES"

THEN...

If CellAA24 Reads YES,...then the text in
Cell C36 in ANOTHER WORKSHEET called SDI Discovery shall turn to BOLD.

Possible? How would I write this out?
I'm gessing that I need 2 separate formulas for this:
One for CellAA24 and yet another for Cell C36.

The less complicated the better!

Thanks!
td