Dada,
I barely know you, but the xmas thing is really tempting, I think I would consider you as my good daughtie at any time.
I don't think that DNA test will be a problem, law is pretty complicated in here and there is always a way to handle it.
I only worried about the age thing, I don't want to be rude, but if you happen to be above my age (or a few years under), I think it will be difficult to explain how you became my daughter, no matter how sinful I were in the past.
At any rate, let's not disregard the marriage thing ... yeah I know I have to divorce first, but you know, everything is changing so fast in these days. ...