The OP is "luring" people with a small amount of information i.e. "bait," and other people will "bite," as a fish would, to learn the rest of the info.
Yeah, I know the phrase. What I find difficult to believe is that three random people responded with the same response on his simple 2 line comment.
I mean we see tons of comments with "small amount of information"/cryptic references that might similarly puzzle people in HN, but not equally many "I'll bite".
"I'll bite" is a pretty common response when someone says something without elaboration that you sense they really want to follow up on. Maybe its a regional thing, but I'm having a bit of a problem thinking of another phrase.
How is that the most obvious response to parent's observation about echo?