what does "rob the cratle mean"

What does it mean when someone says "rob the cratle"? Someone said that to me and I don't know what it means.

If you mean "Rob the cradle," then it means to date or marry someone much younger than you are.

I've also heard this expression to mean dating someone under age (as in legally under age or to put it in another phrase--"Jailbait"). And, I've heard it imply that by robbing the cradle you are robbing the innocence--- because, a sense of their youth is lost and a maturity gap narrows to compensate for the age difference. I think depending on the spoken situation the meaning can "slightly" vary. But, I like the first explanation better than my own.

No, I don't think it is intended to mean dating someone legally underage. This expression is used on TV, for example, often when someone is dating a collage student when they are 30 or so. The term basically means a large gap in ages. It could even mean a 70 year old man dating a 40 year old woman. 40 isn't young, but it's all relative.