Well, you should not have allowed her to be exposed to gambling at such a young age even though there's a chance that she might end up discovering it by herself when she's older but this is better because she would have the mental capacity to handle the pressure that comes with gambling. You can't change what has already happened but you can start guiding her so she won't make mistakes as she gets older
If the father is gambling, it's almost expected that the daughter will at some point see that his father is gambling therefore, she will be curious with it, and will also try it as well.
You've said it that at some point, she will discover it as well, but in a different way and that's true especially now that there are still lots of gambling websites being promoted online, but I don't think it will take too long for her to know gambling just because of how online gambling is being advertised in the PH right now. I agree with what you said that you can't change what's happened, and this is the perfect opportunity for the OP to do his duty as a father. To guide her, and not get addicted to gambling.
it depends there are two sides of it
sometimes we'll see what our parents do and mimic it, be more attracted to the activity, but other times we'll feel repulse about it and avoid it
it'll vary a lot from person to person but it's common to have some kind of overlay with our parents interests but this overlay is never 100%
does it make any sense? do you agree with it?