When CG brings an imaginary creature to life, you can move it at will. But if you bring a toy that millions of children have brought their childhood on the big screen, you have to use every trick to make it as believable as possible – including something as simple as playing with stuffed animals on set ,  BBC Click talked to Chris Lawrence, who served as visual effects supervisor last year Christopher Robin ; a movie that contained photorealistic, realistic versions of Winnie-the-Pooh, Piglet, Tigger, Eeyore, and other characters from the Hundred Acre Woods. The interview that Framestore created for its 3D models of stuffed animals not only includes the amazing amounts of detail effects for visual effects, but also includes a few behind-the-scenes footage showing how things developed on the set.
Bean Bag versions of Every stuffed animal that was covered with tracking markers was used on set when human performers interacted directly with the characters or they stopped to make sure their movements were of size, position and weight correspond to the digital plush substitutions that would be added in post production. But for scenes in which plush figures moved and walked on their own, the performers on set simply played with physical toys, just as a child would do to bring them to life.
These performances and movements were later used as a reference by the artists who animated and added to the scene the digital versions of Pooh, Tigger, and the other toy figures to reinforce the idea that a child's imagination originally came to life has awakened. It's also nice to know that there are actually workplaces that play with toys ̵
[h/t Art of VFX]