Test hatch egg mixed with yesterdays eggs...what to do?

[Tuffoldhen]

I have a Blue Orp doing just that at the moment!!...and its going to be 2 degrees here tonight...she is setting on air and shavings!!....

 

[silkiechicken]

Ouch, yeah, the girl in the pic sat for 6 weeks to get her one chick. Three days before her first batch of eggs were due to hatch, they disappeared!!! Gave her a new one and she spoiled the kid rotten when it hatched 3 weeks later in the middle of winter. It was 40F and raining, and she went out with the 3 day old chick to go scratching and exploring!!!