Belinda and the Missing Will - A Belinda Robinson Novel, #3

Belinda is thrilled that her unusual grandmother along with her equally unusual Siamese cat, Senna, are looking after her while her parents are away. Unusual things always happen when grandmother comes to visit... This visit is no exception. First, a missing last will and testament is all that will save old Miss Higgins, then the petrified gryphon on Miss Higgins' roof accidentally gets woken to life.
Belinda and her friends learn they must find the gryphon's missing ankh in order to learn the location of the will and only then will this hungry, angry gryphon go back to sleep.