If they gave the other children pills too, it would be a bit difficult to claim they ALL got into the pills.
And I don’t know many almost four year olds who would eat pills, anyway.
I only made that suggestion as contrast to how the parents might have explained the presence of sedatives in their daughters system...in comparison to the grotesque theories current.
When my middle brother shared my mother's birth control pills with my youngest brother when we were children, one was 5 the other was 3. All medications were keep in a locked box above the refrigerator. The boys threw the box down several times to get into it.
The Emergency Room was busy that summer.