I couldn't help but notice the nest - the pigeon pair had been roosting on my windowsill for ages and took advantage of a tiny ledge on adjacent scaffolding to build the nest. it took them 3 attempts as the space was so narrow the materiel kept falling off. it gave me weeks of pleasure watching...
I know these are from a previous year (2016) but when I posted the info somewhere at the time - I was told it never happens and I had "faked it" by adding an extra egg - like why would I even bother doing that?? I didn't know at the time how rare it was
Twin Pigeons (feral) successfully hatched and raised by parents from a single egg by my window. Unhatched egg remained in the nest for several days before being ejected.