A Probability/Statistics Question?

Question

My oldest child was born nine years ago on January 26.
My second child was born seven years ago on June 26.
We are currently expecting our third child with a due date of September 26.

My question is, what are the probability and statistics facts for having three children born on the 26 (assuming the baby does arrive on her due date).

Thank you!

Answer 1

There are 12 days in the year that are the 26th, out of 365.25 days (give or take a hundredth or so). So, your chance of all three on the 26th of arbitrary months is 12/365.25 cubed. About one in 28,200.

Now, if you relax it to just "all on the same day of the month" without specifying the 26th, it's about a tenth of a percent.