Q: My husband and I have been married for nine years and have two children, ages 9 and 2. We also have two daughters from his previous marriage. (His former wife left him.) One is 18 and the other is 14. I am having real problems with the 14 year old.

Two years ago, his ex-wife moved out of state and took the girls with her. My husband was deployed to Haiti when she moved. After a couple of months, the 14 year old decided she wanted to move in with us. She has been with us since July 2010.

At first, everything was going very well, and she was on her best behavior. Recently, she's been displaying some very risky behavior — friending random strangers on Facebook and sending her phone number and pictures of herself to them. I've talked to her about the dangers of pedophiles and the fact that you really don't know who's behind that cute boy's profile, all in vain. She has now lost access to Facebook, the Internet and her cell phone.

Since this happened, she's decided she wants to move back in with her mom. My husband's deployed again and will not be back until February. She's determined to move over the Christmas break. We have full legal custody. Legally and logically I know she should stay here. She is a good student for the first time in her life and as I am a stay-at-home mom, she has a lot more supervision than she would with her mother. However, she is a very headstrong girl and will literally do whatever it takes to get her way. I'm worried about drugs, alcohol, sex — you name it. I don't think she would stop at any of it, if it meant frustrating me to the point that I sent her to her mother's. I've suggested counseling to her, but she blatantly refuses to go. Something's going on. She's extraordinarily boy crazy and will go to any length to get attention from boys. Her mother and I agree that she is a predator's ideal victim, but neither of us knows what to do with her. Please help! I'm at my wits end.

A: Dear at My Wit's End,

Legal custody means legal custody. Tell your stepdaughter she can't legally move out of state and you'll have to call the police if she does. Also, explain that you want to make things better for her and work on your relationship together at counseling. Explain that you'd like to give her some privileges back. Since she's still a good student, there's a real chance she won't be entirely derailed by media influences.

You must still watch her carefully. You can give back her Facebook privileges cautiously by insisting that you be allowed to check it randomly. The Internet computer needs to be in a family room where you can keep a watchful eye on her. These are hard times for teens, but if she learns she can manipulate back and forth between her mothers, she'll surely get into trouble.

Stay united and remind her of how much all her parents love her. Try to Skype your husband regularly, so he too can have good talks with her. Don't give up on her. Someday, she'll appreciate just how much you care.

For a free newsletter about "Growing Up Too Fast" (Rodale, 2005) in middle or high school, send a self-addressed, stamped envelope to the address below. Dr. Sylvia B. Rimm is the director of the Family Achievement Clinic in Cleveland, Ohio, a clinical professor of psychiatry and pediatrics at the Case Western Reserve University School of Medicine, and the author of many books on parenting. More information on raising kids is available at www.sylviarimm.com. Please send questions to: Sylvia B. Rimm on Raising Kids, P.O. Box 32, Watertown, WI 53094 or [email protected]. To read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.