"She is the child."
Translation:Cô ấy là đứa trẻ.
Yes, even with the assumptions about pronouns, they should have avoided this one.
Even if a baby talked, he should say chị ấy, (elder sister), instead of cô ấy (aunt), which is what I call my mother in law.
Although I have just thought a case where the phrase is valid. If they are seeing an old photo, the child could be an old woman.