My poorly hen has gone now.  I got her down this morning from where she sleeps and put her beside the water container so that she could have a drink.  Sometime during the day she managed to get up the ladder and laid an egg in the nest box.  She is the only one in that run who lays brown eggs so I know it was laid by her and it weighs all of 10g.  Bless her.  I feel so guilty because she must have put so much effort into laying that egg in the correct place but the growth was increasing so fast now that her whole underneath was dragging on the ground and was plastered in mud.  I know we made the right decision but I just feel so guilty now because of that egg.