(rather than keep on saying "your daughter", I'll just refer to her in the second person below....)
The most likely cause is that the money has been sent to your account by accident (this happens much more often than banks like to admit). If this is the case, then in most jurisdictions (you may want to check further) the money is technically yours. However if the bank know that this was not intended for you then they usually transfer the money out again and claim that it was only a data processing and the money was never really in your account in the first place. And at this point the money is technically 'theirs' and from here anyone with a further claim on it better have good proof that it does not belong to the bank.
As D3C4FF says, it is also posible that her account has been compromised. You should take steps to ensure the account is secure - changing passwords for online services and notifying the bank. In this case you are already 'associated' with the money laundering, but there is a risk that they may plunder your money as well. I wouldn't worry too much about waking up with a horse's head in your bed for this amount of money.
If it were me (and I'm in the UK which has a different banking and legal system) I would transfer the money into a different account at the earliest opportunity, notify the bank and the police that it had arrived unexpectedly. It's then up to the bank to prove that that it's not your money. Give them, say 3 months, then treat yourself!
(but as I said earlier do not spend the money until you've had a chance to verify what laws apply in your jurisdiction)