It seems that this story originated on the film review website of a man named Jon Negroni. The evidence is there, if you look close enough.
- Andy's hat looks more like Jesse's hat than Woody's hat.
-Jesse is pictured with that hat in her previous owner's room
-Jesse's previous owner is old enough to be Andy's mom and has the same hair color.
Unfortunately, Pete Doctor, the writer of several Pixar films has denied any truth to this theory.... but he could be lying right? RIGHT?