Douglas, you were hardly being arrogant. Like I said in my post, as long as everyone involved is being respectful there is nothing to fear. Some people would rather close their minds to the fact that our darling little monkeys like to rub up against each other but those are the same folks that "accidents" seem to happen to (See Palin family for the best example).

You better tell him to be careful with that girl and make sure she's on the pill. Tell him to actually watch her to make sure she takes them. The pill isn't perfect but if most sexual encounters are blowjobs, then there's no need for him to worry about protection. Tell him to tell his gf that if she really loves him she'll have to do a lot of sucking and in return, he's willing to have vaginal intercourse once a week or so.

This will ensure there are no silly, "If I have a kid he'll stay with me!" situations.

I appreciate, Cary, that your first thought was to remind this parent that "a girl" is an individual, and that before anything else you ought to know who, precisely, she actually is! The fact that this young woman was apparently someone the parent had never seen before was the only thing about the situation that really alarmed me. If he had said "his girlfriend" or "a girl from school" or something else that indicated the parent knew who she was would have been quite reassuring.

Now that the secret is out everything needs to be above board. The parents should meet the girl, her parents should meet the boy, the parents should meet each other. I don't think it's asking too much of teens that if they are going to have sex, they do it in a relationship (not a "hook up"), and that all parents be aware of who is dating whom and have made acquaintance with each other.

I wonder what the legal ramifications are, though, for being the so-called "cool parent" who says they can have sex in the family home when they are still minors. Seems like it might be fraught, much as the popular "progressive" thing to do is to say "better to allow it than forbid it."

He says son is going into "Grade 12," a Canadian phrase. (Americans say senior year or 12th grade.) I don't know if the our northern neighbors take such a punitive approach to the legality of underage sex. I'm sure other commentators can enlighten us. Cary's concern about legal liability maybe irrelevant for this particular case.

Give the kid a talk and a sack of condoms. Teenagers fuck. That's what they do. You can't stop it, you shouldn't try. Ground him? Sure. But make sure he's being safe.

I'm quite sure your response would have been quite different. In any case, sexually active individuals of ANY age/gender need to made aware of the consequences: of possible pregnancy and raising a child to age 18 (estimated to cost about $250,000 - and, of course, that doesn't include college); of getting an STD or HIV (which could lead to AIDS); of having the parents of an underage girl having your son arrested, and more.

"What to do?" You've got to be kidding ... you're a PARENT, not a buddy.

Talk to your son. Introduce yourself to the girl and get to know her a little better. Then decide if they are mature enough to handle the responsibility. Children have a tendency to meet their parent's expectations, whether they be low or high. So set them high.

I have 4 teenagers. Although I have been talking about sex, responsibility, yada yada, for years I found that it was helpful to not only talk, but to provide them with a resource they could consult in the privacy of their own room. The book I used was S.E.X.: The All-You-Need-To-Know Progressive Sexuality Guide to Get You Through High School and College by Heather Corinna (I have no personal connection at all). I expect there are other good ones as well.

This one acknowledges that teenagers have hormones, and will want to have sex. It is very straight-forward about the health and emotional considerations and emphasizes the responsibility (both emotional and health-wise) you have for your partner. There is a lot of very straight-forward information about all different aspects of sex. What I liked was that there was a sexual readiness check-list. I handed my kids their own copy of the book with the checklist marked, and said I'd be talking to them about it. Then (individually)I went through the checklist with them, discussing my own personal thoughts about the items, and giving them an opportunity to talk or ask questions. Not surprisingly they didn't say much.

Did this, or will this, make a difference? I don't know, but I do know that I can be sure they know what I think and that they have been forced to consider things at least a little bit.

All that being said, I don't know what I would do if I found a girl in my 17 year old's bed. I'd probably pull out that checklist and go over it with him and then decide.

Or he'll never leave. It sounds as if I'm joking but I'm not. If he has it all -- including sex -- it may be a while before he is motivated to find his own place.

@Nathalie:

LW's Canadian. He says son is going into "Grade 12," a Canadian phrase. (Americans say senior year or 12th grade.) I don't know if the our northern neighbors take such a punitive approach to the legality of underage sex. I'm sure other commentators can enlighten us. Cary's concern about legal liability maybe irrelevant for this particular case.

Nice catch; I'm Canadian and I didn't notice his use of "grade 12", possibly because it wouldn't jump out at me as an unusual phrase.

Until recently in Canada, the age of consent was 14. It has recently been raised to 18.

There are also pretty generous exemptions for people who are close in age. I can understand that some places in the US have an age of consent of 18, but not having exemptions for kids close in age seems completely unrealistic and unfair, leading to situations like a 17-year-old and a 16-year-old both technically being rapists because they're having sex with each other, but the authorities only prosecuting the boy in the relationship for statutory rape.

From the Wikipedia article on this subject (see link in my name):

Although Canada is a federation, the criminal law (including the definition of the age of consent) is in the exclusive jurisdiction of the federal government, so the age of consent is uniform throughout Canada.

The Tackling Violent Crime Act took effect on 1 May 2008, making the current age of consent 16.

There exist two close in age exemptions, depending on the age of the younger partner. A youth of twelve or thirteen can consent to sexual activity with an individual no more than two years older than them. A fourteen- or fifteen-year-old can consent to sexual activity with a partner who is no more than five years older than them.