Broody hen off nest alot day 20

[Ceecee23]

My Broody hen has gotten her babies this far, its day 20 and she's been a good mama, rarely off nest for longer than 20-30 mins. Its day 20 , i heard chirping from one of the eggs, but now my broody keeps leaving the nesting box on off on off all day. Another hen sat on the eggs for a bit . first time with broody hatching eggs. I am freaking out and worried about the eggs getting too cold or the one i heard chirping dying. Shouldn't she be on "lock down" i am not even sure what that means. Help please :/

 

[Ceecee23]

My Broody hen has gotten her babies this far, its day 20 and she's been a good mama, rarely off nest for longer than 20-30 mins. Its day 20 , i heard chirping from one of the eggs, but now my broody keeps leaving the nesting box on off on off all day. Another hen sat on the eggs for a bit . first time with broody hatching eggs. I am freaking out and worried about the eggs getting too cold or the one i heard chirping dying. Shouldn't she be on "lock down" i am not even sure what that means. Help please :/

Its only 53 degrees here. We do have a heat light in coop