I swear, it's a good thing I married someone with such a better memory than me.
Lee told me that Natalie's GI doc didn't say she showed no signs of reflux - he said he saw no signs of abnormal acid reflux. He saw signs of reflux (because everyone refluxes), but saw no signs of acid reflux (ie: her esophagus looked good). And just because he didn't see any acid reflux doesn't mean that Natalie doesn't suffer from another kind of reflux. Or maybe she did have acid reflux, but the Prilosec she's been taking for the past few months has helped. Or maybe she has no problem at all with reflux and we haven't yet found what the problem is. Or maybe there is no problem and she's just a fuss bucket.
Either way, Natalie's pediatrician reassured us that getting the endoscopy was a good idea. And she recommended that we start her on a small amount of rice cereal to see if that helps calm her fussiness.