Just a remainder: https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-believe-about-names/ https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-.

Just a remainder: https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-believe-about-names/ https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-.... Don't rely on first and last names. Also, the age keeps changing, store a date (unless the age is what the user inputs, and is later converted to a date). (#1=(person ...) #2=(person ...) (person :names ("John Smith") :date-of-birth @1993-10-04T05:03:00.000000+01:00 :parents (#1# #2#)))