Dory, Marlin and Nemo already consider themselves in all respects following the events of Finding Nemo. However, Finding Dory explores the lovable Blue Tang's journey towards discovering her biological family while overcoming her memory condition. The movie ended the best way it could possibly have, with Dory finally reuniting with her parents. Apparently, director Andrew Stanton considered introducing a new sibling for Dory, but obviously that didn't make the cut.
In an interview with Cinema Blend during the Finding Dory press day in Los Angeles, the filmmaker explained why he and writer Victoria Strouse didn't include the plot twist in the movie. Stanton said:
I also thought it might be a little bit more of a metaphor for an adoption story. I thought because of the short-term memory loss that the parents might have adopted another stray and kind of misconstrued the loss of Dory. It was very hard to make them sympathetic for making that choice, even though it happened innocently, but that's how it started.
Realistically, it is possible for Dory's parents to have adopted another child in Dory's absence, but ideally, the current plot of the movie works. Clearly, it would be hard for Dory, as well as the audiences, to gulp down the fact that to Dory's parents have seemingly moved on after they lost a child. Add that plot twist following Dory's enormous effort of crossing the dangerous and massive ocean to search for her family, and it would certainly be rough.
While adding an adopted sibling for Dory would sure make for an interesting plot twist, I'm glad the filmmakers didn't take that route. It was more organic seeing the film focused on Dory's struggle with her short-term memory loss and finding her family than having to cope with another family-related issue. Clearly, they decided well in dropping the plot twist. Finding Dory has broken records at the box office already, and I've no doubt it will continue to do so in the following months.
The movie is now in theaters.