Don't count them before they hatch.
And don't let your children write numbers on their little eggs with a purple crayon and then name them Jeffrey and Peeperton and Fluffy and Spot so that whenever you candle them they call them by name.
That way, when they don't hatch, your children won't be devastated because number 13 wasn't just number 13, but he was Peeperton, and Peeperton wasn't the only thing that didn't hatch. The dreams and plans your children had for Peeperton didn't hatch either.
Then there will be many tears, accompanied by burial services and much mourning for what could have been.
That's why you shouldn't count your chickens before they hatch.
Postscript: Apparently, all of the chicks (except the one that hatched) thrived until around Day 18, when they all died. We opened the shells and saw that they were perfectly developed. They had perfectly formed tiny beaks and claws and were covered with little yellow feathers.
We aren't sure why this happened, but have read of several possibilities such as temperature too high or low, or humidity too high or low. We monitored both the temperature and the humidity carefully, and since the one egg hatched, we are perplexed by the outcome.
Post postscript: Alas, our hopes are renewed because Piccolina found a turkey egg at the country club that is now in the incubator. Today is day 4 of the 28 day incubation period for turkeys. We will update periodically.
For any game wardens reading this post, (and what game warden wouldn't want to keep up with a homeschooling, large family blog?) we only found out that it was sort of not legal to take a turkey egg out of the wild after we brought it home and started incubating it. Please, don't prosecute. Thank you.