Thanks! Yeah, I figure Rabadash (really the Tisroc, but he's humoring his son on this point) didn't let Edmund go until at least a couple weeks after the 'wedding,' and then kept a very close guard on Susan until she was heavily pregnant. And once she'd given birth, well, escaping with a child is hard and abandoning one (particularly under those circumstances) is... not a pleasant thought to contemplate. It makes a very effective trap over time.