The mother said she had previously noticed marks on her son and asked Ling whether everything was alright.
Ling told the mother that the marks had been caused by another child who had been pinning children down, scratching and biting them.
Brancis Tamwoy-Mookaa filled in as director at the centre and it was her observations which raised concerns about Ling's behaviour.
Tamwoy-Mookaa heard complaints about Ling's behaviour from other educators at the centre and her suspicions deepened when Ling refused to hand over a crying baby.
She later noticed red marks on the child's skin that appeared consistent with fingernail scratches.
On her final day at the centre, she left a note urging management to check the CCTV footage in the baby room.
The footage was obtained by the ABC’s Four Corners during an investigation into child safety in childcare across Australia
Ling remained at the centre for almost another week before her dismissal.
