Corrected entry: In the scene where Jackson comes home and finds Jack Jr. sitting in the floor crying and Shelby unconscious on the steps, the refrigerator door is open in the kitchen. But Shelby was in the sunroom dressing Jackson in his costume when she became ill. Either she left the refrigerator door open before she went out to put him in his costume or when she went back in to call her husband, she crawled all the way into the kitchen and opened the door, but neither scenario makes sense. Also, she had to go back inside to call Jackson, but he finds her unconscious with the phone back out in the sunroom. She was barely able to move, so it's unlikely that she would take the phone from inside the house and crawl back out to the sunroom with it.
Corrected entry: When Shelby dies, Jack Jr. is about 15 months old and Annelle is pregnant (she asks M'Lynn if it's OK for her and Sammy to name 'this' baby Shelby as she cradles her belly). At the Easter picnic, Jack Jr. looks about 3 years old (it even says in the credits he is 3) but Annelle is just about to give birth to her baby.
Correction: Jack, Jr. was 15 months old when Shelby went into the coma (he had just turned one in July and Shelby went into the coma on Halloween). However, the movie doesn't say how long she was in the coma before she passed away. It's possible she was on life support for months before she died. There was no mention of Annelle being pregnant until Shelby died.
Correction: She had a cramp when dressing Jack Jr, she didn't fully collapse then. It's possible she grabbed the phone and pulled at the fridge as she was heading outside, and was able to walk for part of it. Things being "unlikely" don't make them impossible or a film mistake.
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