The toddler, who suffered catastrophic internal injuries, was found lifeless by paramedics at a home in Arthur Street, Northampton, on December 15 last year.
He was rushed to Northampton General Hospital at 12.30pm but was pronounced dead just 30 minutes later.
Raphael Kennedy, 31 is accused of carrying out the brutal assault on the two-year-old while he was in his care before waiting two hours to call an ambulance on December 15 last year. He denies the charge.
The trial continues.