Does exchanging power include blood? I know it didn't in CCS, but that was between Yue (a created being) and Toya (a human). If Reincd!Syaoran receives Clow's power (though even that's debatable as Yuuko says it's a 'price') via blood, would that make him a blood-relative?

I get the feeling Clamp's been using that term very carefully... well, that or we got lost in translation! XD