Thank you all for informative posts and the great pics Trying and Karen.
mmmm not really sure about the fourth egg remembering last year but if any nest has a good chance of fledging 4, it's this one.
Jane, yes and I think many times we will be holding our breaths. Also it will be interesting to see if 33 will help out with the feeding. On a couple occasions in the past I have thought that he was just about to try but Maya always appeared to step in as if to say "I'll do that". If there are 4 mouths to feed, it certainly would help.
Edit: Morning Cirrus :-)
Maya has just arrived with a large clump of nesting material
c L&RWT
and now breaking it up and fiddling with sticks as 33 incubates
Off for a bit now - SYAL