Aro by law he change you when you were 18.
Emmett your parents agree not not change you unless you found you mate.
Carlisle you were changed after your father found out were had cancer that could not be treated. Your were at the age of 25
Jasper Life you uncle you were not change until you saw your mate
Edward you did need to be changed you were a high breed
victories Due falling of the cliff you were changed a the age of 17
Marcus you where the only thing keeping him on this earth so he had you change at 21
Caius you wee not doing so well. Both he and your mother could not bare to lose you so the both change you. Your age was 19
Jane /Alec it was against the volturi roles but both you and you cousin were 13