Corollary:

n.

1: a proposition inferred immediately from a proved proposition with little or no additional proof
2a: something that naturally follows : 
… love was a stormy passion and jealousy its normal corollary.— Ida Treat

b: something that incidentally or naturally accompanies or parallels
A corollary to the problem of the number of vessels to be built was that of the types of vessels to be constructed.— Daniel Marx