Whether he is 16 or 17, you are a woman, he is a child.

Regardless of what law can be disected, it wouldn't matter to me whatsoever if it were legal or not.

As his mommy, you wouldn't get past me.

Against the law or not.
23 year old woman + 17 year old boy
=disgusting
Grow up!

So you broke up with a guy but now you want to date his brother? Talk about keeping it in the family.

I guess you didn't know that females can be arrested for this behavior just like a guy would. You risk being label as a sex offender or pedophile for life--if you engage in any sexual activities. If you get arrested and go before a judge you can't tell him or her "well he was very mature for his age".

Btw, what state/country do you live?