They all heard that.

And also they heard the answer of the person on the Hippogriff--the person who had snatched Philip on to its back.
'Oh, won't you, my Lord?
We'll soon see about that,' the person said.
Three people there knew that voice, four counting Philip, six counting the dogs.

The dogs barked and growled, Mr.Noah said 'Drop it;' and Lucy screamed, 'Oh no! oh no! it's that Pretenderette.' The parrot, with great presence of mind, flew up into the air and attacked the ear of the Pretenderette, for, as old books say, it was indeed that unprincipled character who had broken from prison and once more stolen the Hippogriff.

But the Pretenderette was not to be caught twice by the same parrot.

She was ready for the bird this time, and as it touched her ear she caught it in her motor veil which she must have loosened beforehand, and thrust it into a wicker cage that hung ready from the saddle of the Hippogriff who hovered on his wide white wings above the crowd of faces upturned.
'Now we shall see her face,' Lucy thought, for she could not get rid of the feeling that if she could only see the Pretenderette's face she would recognise it.