My babies are 3 weeks old now. Brooder is outside but stays between 70-80. They already go up and down the ramp. It has been 60 out so I let them out for a while but they don't always want to go back in. Yesterday they went up the ramp..ate and took a nap before coming back out. Today it was 60 and rainy.... They show no signs of being cold. Q: How long can I leave them out? as long as they like? Thank you all for your great advice.