I saw it at P.575, Harry Potter and the Goblet of Fire.
It is a bit long.
‘He died?’
‘…,’ said Sirius bitterly. ‘Most go mad in there, and plenty stop eating in the end. They lose the will to live…..That boy looked pretty sickly when he arrived. Crouch being an important Ministry member, he and his wife were allowed a deathbed visit. That was the last time I saw Barty Crouch, half carrying his wife past my cell. She died herself, apparently, shortly afterwards. Grief. Wasted away just like the boy. Crouch never came for his son’s body….
P.S. The boy is Barty Crouch Jr., Crouch’s son.