Since Rattus mirabilis is very closely related to R. norvegicus, it too is born with sealed ears, eyes, and even toes, which are stuck together at birth, and it seemed natural that the wings would also be sealed to the pup's back. The aerat litter is much smaller than the Norway's, containing usually two or three pups. Another difference is that a flying rat would necessarily have much better eyesight than R. norvegicus, to whom sight is a luxury. (I'm told that Norways who go blind evince no distress, but they're such stoic creatures that that doesn't actually mean much. Albino Norways are actually nearly blind as a matter of course, and because of it they do this wonderfully eerie thing where they rear up on their hind legs and sway back and forth. The idea, I think, is that they're trying to use parallax to approximate their distance from dimly viewed objects, but it looks like an act of worship.)
When the pups get a bit older their mother starts bringing them chunks of muffins and pizza crusts and whatever else she can gather. Around this time of year one starts seeing the plucky does flapping nestward with dripping ice cream cones and similar bounty clutched in their front paws. The rest of the time they just find the nearest convenient perch and devour the prize themselves.