Certainly they

did not pretend to be sleepy, they were sleepy;
and that was a danger, for the moment they popped off, down they
fell. The awful thing was that Peter thought this funny.

"There he goes again!" he would cry gleefully, as Michael
suddenly dropped like a stone.

"Save him, save him!" cried Wendy, looking with horror at the
cruel sea far below. Eventually Peter would dive through the air,
and catch Michael just before he could strike the sea, and it was
lovely the way he did it; but he always waited till the last
moment, and you felt it was his cleverness that interested him
and not the saving of human life. Also he was fond of variety,
and the sport that engrossed him one moment would suddenly cease
to engage him, so there was always the possibility that the next
time you fell he would let you go.