Found Money and Taxes

This story tells of a woman who is the recipient of some $30,000 found in her house while it was being cleaned by college students due to Katrina damage.

I am sure this istragihtforward, but what is the tax responsibility? Is it treated as regular income? or is it inherited, per the details of the story? Or is there some other category of income it goes in? What if it had been her money in the first place (“Where did I put that thirty thousand dollars? Oh phooey”)? I am assuming that it is liable for some tax,just as I would guess any large sums of found (unclaimed) money would be liable.

My guess would be that it will be treated as income and taxed accordingly. The only way I could see she would avoid that is if she can prove that it belonged to her father (in which case she may be liable for estate tax) or that she herself had placed it in her home and had paid taxes on it back when she originally received it.