He was so full of wrath against grown-ups, who as usual,...

He was so full of wrath against grown-ups, who as usual, were spoiling everything, that as soon as he got inside his tree he breathed intentionally quick short breaths at the rate of about five to a second. He did this because there is a saying in the Neverland, that everytime you breathe, a grown-up dies; and Peter was killing them of vindictively as fast as possible.