The phrase "dree your own weird" comes from Scotland, where they preserve the Old English definition of "weird," as "fate." (The OE word is "wyrd" and in MacBeth, the "Wyrd sisters" are not odd-looking or eerie, but rather sisters of fate. It makes sense, if you think about it.)
To "dree your own weird" means to make your own way in the world, to create your own fate, or sort it out for yourself. As a phrase describing what we have to eventually let our children do, I like it.