Who's older
I always wonder who was older
is Jaken older than Sesshomaru?
is Sesshomaru older than Naraku?
Sesshoumaru is demonstrably much older than Naraku, because Naraku's only been around for fifty years. By the time Onigumo met Kikyou and created Naraku, Sesshoumaru was already an adult.
As for Jaken, no telling.
"You always know where the X-Men have been, because it's always on fire."
- Pete Wisdom