Baby green woodpecker

Last week a work colleague spotted a green woodpecker flying towards this tree and noticed the hole.  I spent over 90 minutes waiting last week and nothing.  I popped by on the off chance today and heard the chick(s) in the nest.  Then I noticed the chick popping its head out so I retreated to about 25m away and waited.  The adult came close, made a lot of noise and flew off.  Eventually the chick started poking out again, so I guess must be close to fledging.