Accused toddler basher faces NSW court

A man accused of bashing a toddler in Sydney's west has appeared in court as legal documents reveal the horrific extent of the victim's injuries.

The 18-month-old boy was found at a Bankstown unit on Saturday night and was taken to The Children's Hospital at Westmead in a serious condition with injuries including a fractured skull, fractured ribs and bite marks.

The boyfriend of the boy's mother was arrested on Sunday morning and charged with four counts of causing grievous bodily harm with intent and three counts of assault occasioning actual bodily harm.

The 20-year-old, who can't be named for legal reasons, appeared in Bankstown Local Court on Monday and appeared to smile briefly during the hearing.

Magistrate Elaine Truscott adjourned the matter until Friday at Burwood Local Court and told the man he would be taken to jail and appear via video link at his next appearance.

"Yes, your honour," the accused replied. He didn't apply for bail and it was formally refused.

Court documents outlining police reasons for denying his initial release shed further light on the toddler's horrific state when authorities found him.

"Police would assert these offences are extremely serious and were violent in the extreme, perpetrated on an 18-month-old child," the documents state.

They reveal the boy's skull was broken into three pieces due to blunt force trauma which also caused a bleed on the brain.

Two spinal discs at the top of his neck were dislodged and he suffered two "distinctive bite marks" on the right upper shoulder - in addition to significant bruising to the face.

Both of the little boy's ears were bleeding, possibly due to burst eardrums, and the tissue between his top lip and gum was torn.

X-rays also revealed a healed fracture on the ribs, the court documents state.

A large group of supporters of the victim's family attended court condemning the accused with offensive language as they left the building.

Police argue the prosecution case is strong because the man was the only one home with the toddler who'd been seen in public - without injuries - several hours earlier.