a young what?

a young what?

Observation - a young what? - UK and Ireland. Description: found this bird in the garden under a window, not stiff yet, but dead. eyes still bright , some tail feathers are still forming . lots of pigeons, starlings and sparrows for food , looks like it was after the sparrows etc that nests in thick ivy on the b

found this bird in the garden under a window, not stiff yet, but dead. eyes still bright , some tail feathers are still forming . lots of pigeons, starlings and sparrows for food , looks like it was after the sparrows etc that nests in thick ivy on the building. just a beginner, now life at a end . saw the adult taking pigeons since the winter, i noticed the very long yellow legs on the adult . none of my books confirm what the birds are, too big for a sparrow hawk, adult was bigger than a pigeon.