My cousin has chickenpox and i came in contact with him. when will i break out in the rash?

In 2-3 weeks: The incubation period usually is 14-16 days and occasionally is as short as 10 days or as long as 21 days after contact.

Depends: At a listed age of 37, it is likely you had it as a kid and are not susceptible.About 96% of adults who do not remember having it test positive for immunity.The incubation period for those who are is 10-21 days from first contact until the rash appears.