Complex sentence: Danni died probably before Otto turned three, as from the small snippet in "Otto Hangs Eleven" of Otto's third birthday party Danni was nowhere to be seen on the other hand, she might have been the one taking those pictures.
Split into simpler sentences: Danni died probably before Otto turned three, as from the small snippet in "Otto Hangs Eleven" of Otto's third birthday party. On the other hand, she might have been the one taking those pictures.