So, yesterday i snuck into the duck house while her highness was in her personal bath-tub and tried to candle the eggs and took some pictures:
I can't see anything else but a black mass filling the egg and the air bubble. Does that look correct to you?
Around day 19 - i don't know when she has exactly started to sit.
I haven't seen any blood vessels inside the eggs, in fact i haven't seen anything but a dark mass inside, but it wasn't very dark in the duck house. When it is dark i cannot get my hands on the eggs because Katy is sitting and she has developed sharp toe-nails…
I guess she will know if there is something wrong with an egg and kick it out, would she?