I'm sorry to hear of your dilemma.
First of all, thank you for serving our country.
Yours is a precarious position, because your husband has no legal right to custody and control over your daughter. And while you may have primary residential custody, your ex no doubt has shared legal custody.
While he can not force your daughter to live with your husband while you are deployed, he could force her to live with him and his wife--out of shear belligerence.
I'd suggest that you might tell him that he has two choices. He can either allow her to stay with the friends, or he can take her in. That might force him to capitulate to your way of thinking.
Alternatively, the fact is that if she doesn't tell him that she is there, perhaps he won't find out.
The reality is that regardless of what you might do, he can always go to the court and demand custody while you are deployed, and as the natural parent, the court would grant it.
If she were my daughter, I'd tell her that she can go, but that there is a risk that dad will petition the court to force her to live with him when he finds out, and that is her risk--the alternative being to stay with your husband.
I wish you and your family the best in 2010.
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