That's horrible to hear man. But do you remember the HR person telling you about their policies?
I work at lowe's....and if you don't remember, you signed an agreement with them, if you don't call for 3 days, you're fired. I just did this, as I was told to resign so I didn't go in for 3 days, and when I get back from break I get re-hired.
They literally told me this is the policy. No matter what, your house burns down, etc, if you don't tell them for 3 days and don't show up and clock in, you'll be deleted, literally. They dont' care.
I honestly think you should sue, because under your circumstances there isnothing you could have done. Then maybe next time I'll get me some fucking holiday pay and be on inactive leave and not have to resign like I was forced to.\
Edit: Your dad called in for you. That is a part of the contract. If someone calls in on your behalf and tells them you won't make it, they have to tkae it as your word until further notice, like you said. Why do I know this? I was real sick last year and was puking like crazy, and my mom had to call in on my behalf and everything was dandy until I called them and told them I was better, aka the next day.
Sue my friend Sue!