The girl is being kept at a women's centre in Thalassery for the last few days. Her mother has not taken a stand on the issue.
The girl first confided in her teachers, who called the police. The father and uncle were arrested and a case of rape registered against them. The girl's 15-year-old brother was sent to a juvenile home.
The police also found that the victim's older sister died two years ago - she allegedly committed suicide. An investigation has been started to find out if she too was abused by the men of the house, but the police haven't found anything suspicious so far. The police has said that there is a fourth accused in the case, another of the victim's uncle who is on the run.
The child reportedly told her teachers that her sister killed herself to escape similar abuse.
"It is very sad that the mother is also not coming forward and reporting the case. This shows the situation in the house. She might be afraid of her husband," Ms Rosakutty said.
The commission has offered to take the girl under its care. Ms Rosakutty said it might write to the chief minister for an enquiry into the older sister's death. Congress activist Suma Balakrishnan has also approached Home Minister T Radhakrishnan seeking a thorough probe into both the cases as well as the arrest of all those involved in the two crimes.
"This is a shocking case of two minor sisters being raped by family members. The police say the older sister committed suicide. But this needs to be probed as no proper enquiry was done," Ms Rosakutty said.
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