Noun+たる/たるもの
Meaning: (Those) who are ….Should; (that) which is ….Should
内科の医者たるものが、栄養のことを気にかけないのは理解できません。 I can’t understand why a doctor specializing in internal medicine does not focus on having a healthy diet.
親たるもの、子どもが悪いことをしたときに、きちんと叱るべきだ。 As a parent, one should properly discipline their children when they misbehave.