Monday Puzzle

The Presurfer, in cooperation with pzzlr.com, brings you a puzzle every Monday. Just to tickle your brain.

image credit: Joey Gannon cc

Two brothers are scrupulously truthful, with one exception: Each lies about his birthday on his birthday. On New Year's Eve you ask what their birthdays are. The first says 'Yesterday' and the second says 'Tomorrow.' On New Year's Day you ask again what their birthdays are. Again the first says 'Yesterday' and the second says 'Tomorrow.'

What are their birthdays?

You can find the answer here.