Assume that, for the most part, Napoleon's career goes relatively historically. Just that his child by Marie Louise is a daughter, rather than a son. We'll assume this daughter doesn't necessarily die at 21, like Nap2 did. What happens to this girl, what does she do? Its unlikely that anyone will be championing her claim to the French Imperial throne, but perhaps one of the Bourbon or Orlean monarchs could marry their heir to her, to try to firm up support for the dynasty?