Actually since the Mom and Dad had the same birthday at the time of their marriage (odds of that occurring randomly would only be 1 in 365) the chances that their baby having the same date of birth (assuming they didn't plan the pregnancy to increase those odds) would only be 1 in 365.
Not quite a miracle. Just a coincidence.
And the odds could be tightened up significantly if they had planned the conception based on the expected birth date.
That’s one way to look at it. But I don’t think that’s the odds they are talking about. ^_^