It was right after she had showed her mother the doll that they heard a knock on the door and when they answered it they see that it's Rachel's aunt and her toddler son.
Rachel's aunt Alice had reminded them that when Rachel's birthday that she had been out of town. That today they were going to go get a present for her. While Alice had been talking that Rachel had become younger. But what was even stranger is that even though she looks like she's 10 her clothes are what a toddler would wear.
We hear Rachel's mom tell Alice she has to get Rachel changed and then they will be ready to go. Rachel's mom takes her up to her room and we see that it has changed to look like a toddler's.