I missed the molestation. Mainly because I only read the first paragraph. To my shame, I jumped to a wrong conclusion about how it was going to go and dismissed it.
I assumed it was the ranting of a disturbed child who was about to do herself in. Horrific enough, but up to that point in the story, not enough to make me want to get to the punch line.
Having read Teresa's analysis I now see I was a bad lad - for which I apologise profusely - and that the story had much more to offer.
However, I don't think this new insight would have swayed my vote.
I think the the problem may have been the layout.
I hear the door open...
Allowed me to break concentration and gave me the opportunity to skip.
It's possible that without these massive pauses I would have read to the end.
In fact, it would probably have read more true to life, if the father returning caused panic and a rush to the end. I fancy that is the more likely outcome of the situation you set up.
Similar to the panic instilled when anyone finds themselves up to 'no good' and on the point of discovery.