Now, I’m a father, and my 17-year-old daughter is starting to gamble too playing slots and even doing some sports betting. I don’t know how to feel, part of me feels oddly proud of what she’s doing.
Gambling is supposed to be from 18+ but since you Said that your daughter is still at the age of 17 this means that she may not be gambling responsibly and there's every possibility that she will definitely become addicted to it, and I guess you know the implications so I will advice you stop her from gambling because she's too young to engage herself into such active so the earlier you do this the better for her.
What does that make me?
Well I can't possibly say that you're a bad father because kids sometimes can be very stubborn especially those within the range of 15 _17 because if you try stopping them from doing so, it will look as if you're depriving them from not having fun. But you need to let her know that aside from gambling there are other means of having fun. Maybe you should try to introduce one of this to her, because you may think that since she's just gambling for fun that there may not be a problem, but I want to tell you that as time goes on she won't be having that same mindset, So I think this is the right time for you to tackle her before she will get used to it.