In Visible Darkness

Slowly, the thing - Tracey could think of no other name for it, though her mind screamed "Timmy, my baby! My little boy!" - removed it's hands from a gaping cavity that it had gouged in Rick's chest. The visible darkness was decaying and an ashen light began infecting the apartment. It was this light which showed Tracey a glimpse of white amongst the red - an unbloodied portion of rib or sternum - and something small pulsing with regularity - Rick's still beating heart.
The thing that was Timmy turned, and slid off Rick's body. Turned, and reached out it's arms for it's mother.