A 51-year-old man has allegedly stolen two mobile phones belonging to a hospital patient injured in a car crash on Christmas Day that killed his wife and daughter, police say.

The Tritton family from Narangba, north of Brisbane, were driving along a main road at Manly West when their car was struck by another vehicle that crossed a median strip.

Police have confirmed that 18-year-old Makayla Tritton and her 56-year-old mother, Karin, were killed in the crash on Christmas Day.

Makayla Tritton died at the scene and Karin Tritton died later in hospital.

The father and his eldest daughter were also injured in the crash and remain in the Princess Alexandra Hospital in Brisbane.

Police officers and other emergency personnel at the crash scene had said they were left traumatised by the crash.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 51 seconds 51 s Police left traumatised after double fatality

Police have alleged Mark Graham Newstead was a fellow hospital patient when he went into the injured father's room and stole two mobile phones.

One phone belonged to the father and the other belonged to his late wife, but both phones have since been recovered.

Mr Newstead then allegedly stole a wallet from another patient, before going on a spending spree at nearby shops.

He was arrested over the weekend and charged with numerous offences, including two counts of stealing, fraud and drugs offences.

He appeared in Southport's Magistrates Court this morning wearing a white hospital gown.

His lawyer argued for bail so Mr Newstead could receive treatment for mental health issues.

This was denied due to Mr Newstead's extensive criminal history.

Mr Newstead was remanded in custody to reappear in the Beenleigh Magistrates Court by video link on January 19.