Barranquilla-based graphic designer Geraldine Fernández claimed she contributed 25,000 drawings to the film's production.
Hayao Miyazaki’s The Boy and the Heron will premiere in Colombia on January 25. Ahead of that debut, the film is getting an unplanned and likely unappreciated marketing push, as a local woman has gone viral for convincing major media outlets that she drew around 25,000 frames for the film’s production.
As far as I know no, in traditional animation every frame is done in one go, except when there's CGI involved (and even in that case there's just one person "drawing").