The probability in question is from the birthday problem, famous in any probability class.Strangely enough, statistically it is very likely for at least two players to share the same birthday in each club. There was an infographic about PL players' birthdays I saw a long while back that reflects that. Fun fact.
Cancelo and Laporte shares same birthday too :D Interestingly, 27th May, 1 day before the trio.
A group of 23 people has about a 50% chance of having atleast one overlapping birthday... BUT
Most of that probability is associated with 2 overlaps, 3 birthdays overlapping is drastically less.