Hermione in Ginny's year (?) and Ginny's birthday

[Sofie]

No: HPFGUIDX 28197

Hi All,
Out of curiosity if Hermione was born in 1980 (which I don't think 
she was) would this mean that really she should be in Ginny's year? 
And by the way do we have any idea of when Ginny's birthday is 
because she has to be at least 9 months younger than Ron? So that 
means she must have been born between January and August 1981. Am I 
right that ron's birthday is in April?

Sofie (a H/H, D/H, R/H, H/G D/G shipper because teenagers go out with 
a lot of people (but Hermione and Harry will end up together!), Draco-
will-be-redeemed (or I will cry), pro-1979, Snape-is-not-a-vampire, 
small Hogwarts amd what does OBHWF stand for?)