Please send your questions for publication to prudence@slate.com.

Dear Prudence,

A few months ago I decided to send my ex-husband a book I'd read, simply because I thought it would interest him. In an e-mail to him at work, regarding another issue, I mentioned that I'd mailed said book. A few hours after sending the e-mail, I got an e-mail from his wife (!) saying, "For the love of God, [insert name here] would you stop sending my husband gifts?"

Though her reaction would indicate that I send her husband weekly tributes, such is not the case. And I don't consider a used book to even be a gift. I've always felt I should maintain a friendly relationship with my ex, for the sake of our son. I also, up until this incident, thought very highly of his wife. At the time of this incident, my ex had no comment nor did he respond to my question of "What gives?" More recently, when pressed, he said that his wife is "funny" about my treating them like normal people. Was what I did so wrong?

—Maddened in Lafayette, La.

Dear Mad,

Hmmm, many ex-wives throw the book at their former spouses, whereas you merely sent one. And, no, you didn't do anything wrong if you've reported the episode accurately. (Some ex-wives drum up excuses to be in contact for the sole purpose of annoying the new wife.) Your successor is obviously thin-skinned where you are concerned—not all that unusual if the new wife is insecure or jealous of any residual affection for the first wife.

The e-mail she sent you seems rather intrusive, if not ball-busting, but forewarned is forearmed. When you need to communicate with your child's father, call him on the telephone—at the office—and ix-nay on the e-mail. It sounds as though he has his hands full. Too bad this is the way it is, but this is the way it is.

—Prudie, knowingly

Dear Prudie,