Will Winterfell still need a maester once it has both a Bran and an Arya?

While Bran could certainly handle the ravenry and Arya has some knowledge of gross anatomy and poisons, I don’t think they could substitute for the more comprehensive education of the Citadel. 

Moreover, I would imagine they would both have a lot to do that would take them away from the more day-to-day management of Winterfell.