He's going to figure out to get past that...right quick. Everybody lies, mainly to themselves. Actually Henry's been doing a great job of it for a while now...but I cut him some slack, he's only 11.

That said, Emma and her secret power being the ability to see through liars is actually a nice tie-in to Henry's neurosis, and possibly why he counted on her never to lie to him.

Yet...he does catch her in a lie in S1 and goes all nuts over it, until she covers and convinces him that she just was fooling Regina.

If I was Regina - I would find a way to catch Emma in another lie - in front of Henry.