I have a pair of silkies and the hen has been sitting on just 1 egg the whole time, is it normal just to have 1 egg? Also the egg is due to hatch this weekend, I want the hen to look after the chick naturally like in the wild and I have not got a heat lamp. Should I go and buy a brooder/ lamp in case or would my hen keep the chick warm? Please can someone help with this so I can be prepared as this is my first ever chick. Thanks