[1] "kid"
[1] "age"
[1] "age"
[1] "age<-"
[1] "age<-"
[1] "name"
[1] "name"
[1] "gender"
[1] "gender"
[1] "haveBirthday"
[1] "haveBirthday"
[1] "show"
Alice F 11 
[1] "Alice"
[1] "F"
[1] 11
Alice F 12