Toddler critical after near-drowning in Sydney's north-west

A toddler is in a critical condition in hospital overnight after he was found in a backyard swimming pool in Sydney's north-west yesterday.

The two-year-old boy was rescued at a home on Castlewood Drive, Castle Hill, just before 4pm on Saturday and airlifted to hospital.

He was still in a critical condition at the Children's Hospital at Westmead on Saturday evening but due to privacy restrictions, his current condition is unknown.

The boy was believed to have been in the pool for five minutes before he was found, the Seven Network reported on Saturday.