I'm afraid you just have to be philosophical about baby birds, especially the common species. Blackbirds usually produce 2 or 3 clutches of eggs each year, sometimes a fourth. Each clutch is 4 or 5 eggs. If the vast majority of them didn't succumb to cats, dogs, rats, sparrow hawks, crows, cars, drowning in water butts and washing up bowls left carelessly in the garden (yes, that one was ours) every year would be like a Hitchcock thriller.
Last year, in Priory Park, I saw a duckling, a few days old, which had become separated from its mother. It carelessly strayed too close to another female mallard, whose own ducklings were rather older. She killed it.
