Introduction (important)

Louis and Harry are parents and the other 3 boys (Zayn, Liam and Niall) are their adopted sons.
this is the ageing that is going to be followed for the 'Kids'. Last name is 'Stylinson'

Liam - 15 years (turns 16 mid book)
Niall - 8 years
Zayn - 3 years (yes he's a baby)