A mystery with dates....what are the chances? What are the chances that 5 dates, from 5 different years, in 5 different months, would all fall on the same day of the week. For back ground my daughter, my son, myself and my wife's birthdays all fall on the same day of the week. To throw another brick in the wall our wedding anniversary also meets this and falls on the same day of the week as all of our birthdays. The probabilities of this intrigue me but I am far from a mathematician. Please enjoy this rabbit hole of quandaries...lol

This event is highly unlikely.  If we assume that all seven days are equally likely, then the probability is $$\frac{1}{7^4}=\frac{1}{2401}\approx 0.0004$$
or less than one-twentieth of one percent likelihood.
To calculate this, let the earliest of the five events be on an arbitrary day of the week.  Now, we need the other four events to be on precisely that day.  Each has probability $\frac{1}{7}$ of doing so, and we need this coincidence to happen four times.

Do keep in mind, however, that you might be suffering from selection bias in witnessing this.  There are not only five important events in your life, so perhaps what happened is that out of thirty important events, five happened to fall on the same day of the week.  The probability of this coincidence is much much smaller.
