We have a robin nesting quite low in one of our maple trees, she laid three beautiful turquoise eggs and was patiently sitting on them to hatch.
Three days ago the nest was abandoned, one egg was broken and half of it was on the ground.
Seems like there was nothing doing after sitting a week on them, I believe the frosty bitter weather and the low supply of sustaining food with the cold, delayed the seasonal progress.
She was very industrious building the nest and did all the right things, egg laying and trying to hatch out young but to no avail, no doubt she will start again when the weather warms up. The adults do sense when there's something not right.