FWIW...

My usual approach to those tricky sex questions is to give them short answers containing any info they specifically ask for--using the clinical terms for body parts, nothing cutesy or incorrect--but no more. If they keep asking, I keep answering. But the second they stop asking, I stop talking.

For a 4yo, I'd probably respond that a Mommy and Daddy have a special hug they use to make a baby. If he pressed on, I'd explain interc0urse in the simplest terms: pen1s meets vag1na, and that it's something only people old enough to handle a baby should do. (Values teaching, too...) Nothing more.

That was the response that satisfied my kids and wasn't too much detail for them to handle. And I think it's good that they will know that they can't get a girl pregnant by kissing her or any of those things that so many kids think.

Kriston