I'm having a hard time agreeing with many of the posts here.
Basically - here is an opportunity for a band to on-board a young, reportedly very talented young woman, in what is THE MOST IMPORTANT ROLE IN THE BAND. If she's really that good, she could very well be the whole key to more and better gigs. She is your meal ticket. If I were in the position of bassist in that band, I'd be working to get her to sing an increasing share of the songs and working to tailor the setlist to fit her talents and preferred songs. Of course, there are the dad/daughter issues that may come up - but also maybe not. Most dads are going to work to elevate their kid - and if she's that good, well, it's a win. Different dynamic than the husband/wife thing that so often blows up. It's worth a shot. Then, I'd lay back and groove my way into more gigs in better rooms and contemplate breaking into the local festival circuit. Of course, I say this as a resident of a fairly rural/tourism-based area that struggles to produce an adequate number of local musicians in general. Maybe in larger markets, talented young female singers are clamoring to play in cover bands, I don't know. That's not the norm here....