OKay, so take your favourite quote from the books and put Jo in it. A few examples are:
[DH, Rita Skeeter to Betty Braithwaite]
'Yes, Rowling [Dumbledore] is a biographers dream. Such a long, full life!'
or perhaps:
[DH, Enid Smeek in The Life and Lies of JK Rowling, by Rita Skeeter]
'Course, with her [his] mum and dad gone you'd feel sorry for her [him] only she [he] kept chucking goat dung at my head!' about Aberforth Dumbledore.