Well, everyone has had a chance at it by now.
The puzzle concerned a woman who apparently had 4 (or 5) children, born in consecutive seasons, with the oldest under one year of age. A lot of people jumped to the conclusion that this was a February 29 puzzle. But it wasn't. The straightforward answer to the Five Seasons version is:
Winter1 and Spring: a set of twins, born straddling the 1994 vernal equinox
Summer, Fall, and Winter2: a set of triplets. Conceived a couple weeks after the birth of the preceding pair [unusual, but not impossible]. Summer is found to have a life-threatening birth defect and is delivered prematurely, by Caesarean, at 24 weeks gestation, just before the autumnal equinox. [You may have read a recent newspaper story about a twin being delivered early in similar fashion; this, in fact, was the inspiration for the puzzle. No reason in principle why it shouldn't happen with a triplet.] Autumn and Winter2 are carried almost to full term and are born straddling the 1994 winter solstice.
There you have it: 5 babies born in different seasons in 1994. Unusual, hard on the mom, but not, I contend, impossible.
American College of Healthcare Executives
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