;; during class, many of you wanted to be able to globally define 
;; the person created in add-child-to-mother.  Here is a version that
;; lets you do that, with an example of how to use it.

;; add-child-to-mother : person string -> void
;; create new person with given name and mother and add new person to 
;; given person's kids
;; EFFECT: changes kids component of given person
(define (add-child-to-mother aperson aname)
  (local [(define childper (make-person aname aperson 'unknown empty))]
    (begin
      (set-person-kids! aperson (cons childper (person-kids aperson)))
      childper)))

(define-struct person (name mother father kids))
(define Brendaper (make-person "Brenda" 'unknown 'unknown empty))
(define Judyper (add-child-to-mother Brendaper "Judy"))
(define Eddieper (add-child-to-mother Brendaper "Eddie"))
(define Fredper (add-child-to-mother Judyper "Fred"))