The tot passed away after he was left in the family's SUV in a church car park during a blistering heatwave in East Dallas, USA.
His parents were alerted the boy was missing by a fellow church member during a service at Rehoboth Praise Assembly on Sunday afternoon.
The next thing the congregation knew the father had brought the little boy into the church - but it was too late.
Church member Reng Om told CBS Dallas :Officials have warned about leaving children in hot cars after a four-year-old died when she was left in a car in Pennsylvania last week.
"He was grabbing his kid, and the kid would not move, and saying 'I need somebody help, call the police." I think he wanted to call police but he doesn't speak English.
"They are a perfect family. I'm very upset for him.
"The kids like to read the Bible. I'm really upset for family."
Om said the parents discovered their son wasn't with their other four children when the youngsters emerged from a bible study class.