MULTI SHEET- populate a cell in results sheet with last entry from previous sheets

Hi,

I am trying to get a cell, lets say A2, on Sheet 5 of my log to be equal to the last non blank or greater than zero entry in cell A2 from Sheet 1 through Sheet 4.

Example: sheet 1 cell A2 = 5, sheet 2 cell A2 = 1, sheet 3 cell A2 = 3, sheet 4 cell A2 = blank.

The value I want in cell A2 of sheet 5 is 3. Any help would be greatly appreciated.