wiht an 8+ year diffrence between TDk and TDKR, and an unknown period of time between RDK and BB, (Long enough for an election, but not long enough for the Batman to have caught the Scarecrow yet...) I'd say it seems unlikley. Not enough time for little blonde kid to grow up.

Also: I'd expect that Blake's parents were already gone by this point, and that he was in a Boy's home. IIRC, we hear an adult's voice ofscreen in the scene with this kid - suggesting he's at home with a parent. (Though, that may be my memory messing with me. I can't confirm right now.)