If she were, Andy's Mom would have likely known she was from Woody's Round-Up and would have told Andy as a kid that he had a toy from the show too just like she had Jessie.
But this could be the reason we are never told the name of Andy's Mom so it's up to each and their own to decide whether or not she was Jessie's original owner.
You don't know whether or not Andy's mom told him that. In Toy Story 3, Andy knows Jessie's name is Jessie. The only way he could know that is if his mom told him, or if he was familiar with Woody's Roundup. My guess is the former...
shareWe never know, disney won't tell us. But if she was she most likely forgot about Jessie and her younger years, probably why she never noticed Jessie when andy is playing with them
shareIf she was Andy's mom then Pixar would have covered it by now. They have even been quoted in saying that Andy's mom is not Emily and never will be.
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Solving Plot Holes 101: Learn to use your Critical Thinking skills.
^This.
"What do you mean 'parodies are exempt' from copyright law?"-J.R.R. Tolkien on Bored of the Rings
Also, people saying, "Oh, how did Andy know Jessie was named Jessie if she didn't belong to Andy's mom!" are missing that Andy also calls Bullseye by his name--Bullseye didn't belong to Emily. He could have looked up the "real" names on the internet. (I know our family had a home computer with internet in the mid-90s.)
And this movie is designed with children in mind. Kids would get confused if Andy referred to them by different names outside of one of his play scenarios.
You're a sexual Disneyland.share