Family advice: My sister tried to cover up her daughter's troubled past. Now it's about to blow up.

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Dear Prudence,

My niece has always been troubled. She got pregnant at 14 and ran away at 16. She died of a drug overdose at the age of 25.

Her baby, “Jenna,” was adopted by her grandparents—my sister and brother-in-law. They decided to lie and pass Jenna off as their own child, and have never told her about her adoption, and use the experience of her “sister” in order to scare Jenna into obedience.

Jenna will be starting high school next year and has been stretching her wings and butting heads with both her parents. She has also been digging through family history and asking questions like why there are no pictures of her mom pregnant with her. My sister is just stonewalling, and I am very afraid of how badly this