The stepfather allegedly assaulted the baby with a firewood for urinating inside the house. The child has injuries on left shoulder and hand. Lips and face are also swollen.
Doctors who examined the child found the injuries on the girl were inflicted with sharp tools.
Authorities who inspected the body found scars of earlier torture on the girl’s chest and back.
Wounds and injuries were found on the child's private parts in the examination carried out by the surgery department.
The assault came to light after the girl, staying with her mother, brother and grandparents, told about the abuse to one of her relatives 10 days ago.
The woman, who was granted bail by the Kerala high court recently, has claimed she was innocent and that she had been framed by her estranged husband and his second wife.
The woman said her husband had wanted custody of their son. When she refused, he had threatened that he would take the child away at all cost.
The court directed her to furnish two sureties of Rs 1 lakh and also instructed her not to make any interventions that could influence the probe.
Though the couple had a love marriage, the woman has been living separately for the past three years owing to marital discord.
Drama artist Sasikumar masqueraded as an ex-serviceman and suppressed information about his marital status while adopting the girl with the intervention of the Council.