I have 3 hens that have been sitting in their boxes and producing infertile eggs (one rooster is too old and 5 are too young). I put a few duck eggs under them and after candling them, I have 5 ducklings to be! It has been getting down to 30-40 every night and staying about 70 during the day. It will be much colder by the time they start to hatch (2 are due about october 5 and the other 3 should be the 12th). I would hate to seperate the little babies from their "moms" but would a brooder in the house be a safer option?