The Water Horse by Dick King-Smith (Paperback)

Is it a beastie? Is it a kelpie? Is it a sea monster. Angus and his sister, kirstie, have found something strange at the beach so they take it home to put it in the bath - who knows what it might be? At first they think its's just a big old piece of seaweed, but in the morning it's squeaking and splashing ... the seaweed has hatched into a curious creature with little flippers - it's the water horse! The question is will Mum let Angus and Kirstie keep him - and what whill they do with him if he just keeps on growing?