If the "iPhone Unavailable" screen says "try again in XXXX", that means that your daughter still has a chance to unlock the phone without losing her data. The timeouts get longer and longer the more incorrect attempts you make, so if the phone says "try again in 8 hours", she only has one more chance to enter the correct passcode.
If there is no "try again" message and there is no "Forgot passcode?" option, the only way to get back into the phone is to reset it. That will wipe everything on the phone (which may already have wiped itself).
The "Forgot passcode?" option only appears if you have changed the passcode within the last 72 hours. I am guessing that isn't the case here.