I was thinking along these lines when I watched ep27 (about fifteen minutes ago). There's so many hints dropped (Izumi can't have children? Is that what they're implying when Winry's question is avoided? Hence her fierce protection of the boys and her later reaction? Is it the thought that they'd try and transmute her corpse [as their secondary mother figure] if she were to die part of her fear and intense anger at their actions?) and so many undercurrents going on. There were a couple of people at my anime soc who were quick to dismiss FMA as the standard AU, boy-cum-hero fare, but they're missing the point so badly. There's so much more to this series than that. And ep27 is a brilliant example of this.
I was clutching at my heart when Ed confessed about transmuting their mother. Then when Izumi hit him... that's when I cried. Cos they've done something they truly regret and no matter how hard they repent they can never take back that sin. It doesn't matter how hard Izumi beats them - they've already learnt the lesson, and it doesn't change the past. And truth be told that's why I believe they'll never get their bodies back. At least, Ed won't. It doesn't matter that they're sorry. They're branded for life.
On a more pleasant note, did people notice the way Izumi's fingers were threaded through the segments of Ed's braid when she hugged him? Ngaahhh! What I wouldn't give... *dribble, dribble*