I would say because they're in a set of triplets? This is because there are three babies that are born from the same mother on the same day, and two of those babies would be born on the same day... but they would have to be twins... so it isn't possible unless they are triplets.
you would contact what ever you were apart of and state the issue and if they dont call someone higher and if nothing gets fixed then looks like something can be brought to court