PLEASE HELP! My Brother Is Sleeping With His Daughter, What Should I Do?

Please help me as this is very urgent because I am in a confused state and do not know what to do.

My brother’s wife called me yesterday to report my brother, she said their daughter called her two days ago about what her dad has been doing to her.

She told her that, her dad has slept with her twice, so the mother called me to report the case that she’s confused and doesn’t know how to confront her husband.

The daughter said the first day he slept with her was when her mother went on a night vigil in the church.

The second time he left his room in the middle of the night pretend to go and urinate and went to daughter’s room to sleep with her for the second time.

He has threatened her not to tell anyone.

Honestly, for the past 2 days I couldn’t sleep, was just thinking about how to approach the situation and how to rescue the innocent girl from her abusive father.

The girl is around 17 years old.

I stay in Lagos while they are in Abuja.

I Need Your Immediate Advice, Please!