Police investigate death of three-year-old girl at Glenmore Park

The death of a young girl at Glenmore Park, in Sydney's west, is not being treated as suspicious. 

Emergency services were called to a family home at 5am yesterday, with initial reports suggesting the three-year-old was ill and suffering from a fever.

Paramedics arrived and found the child in cardiac arrest.

They performed CPR all the way to Nepean Hospital, but she could not be saved.

Neighbours have told 9NEWS forensic officers were in and out of the house all day.