It was the faint hum of the blue green glow that first drew him to the baby's room that night, a glowing shimmering aluminum clam shaped thing was parked outside It had long metallic arms and had lifted the child up turning it slowly as the creatures transformed it. They weren't much bigger than ants and glowed in the dark of the room making luminous trails between the sleeping child and their mothership and he could see it was already too late. His sleeping son Johnny had been transformed in to a complex space machine. It was then he began screaming, no one believed him and said that he had lost his mind but he knew his son had been taken over by aliens.

Excellent sci-fi story.