The Fortress of Kaspar Snit by Cary Fagan

From chapters.ca:
Kaspar Snit is a villainous villain who is determined to steal all the fountains in the world. Why? Fountains are beautiful and give people pleasure, two things he can’t abide. Can a family of four who love fountains rescue them from the hands of this dastardly scoundrel? Especially when that family is made up of the four most eccentric individuals you’d care to meet? Eleven- year- old Eleanor, eight- year- old Solly, better known as Googoo Man, and their parents, who are, to say the least, odd, set out on a hilarious quest over mountains and across the seas to storm the fortress of Kaspar and retrieve the lost fountains. Cary Fagan’s first novel for children is a fun fantasy that will keep young armchair travelers laughing right to the exciting end.