Why do babies die. Because:
Heb, 9:27 And as it is appointed unto men once to die (< which I think was appointed before the foundation of the world, otherwise how could it have been appointed for the Christ, as of lamb, to shed his precious blood, before the foundation of the world?), but after this the judgment:
He was created, is born, that way.
Forasmuch then as the children are partakers of flesh and blood, he (the Christ) also himself likewise took part of the same; that through death he might destroy him that had the power of death, that is, the devil; Hebrews 2:14
How could the Christ come in that manner, for that purpose, had not the first man, Adam, been created that way?
He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil. 1 John 3:8
God created the first man Adam, for the purpose of the manifestation of the Son of God, in order to destroy the works of the devil.
The devil was and had been doing his works before God planted a garden eastward in Eden and put the man he had created in the garden where, Satan, the devil, that old serpent, already was.