Assalamu alaikum wa rahmatulahi wa barakatuh,
Indeed, it can be distressing to find out that your child is smoking and you are right to be concerned. It is obviously more difficult to address it with her when her father and his wife are also smokers, but nevertheless needs to be addressed. There a couple of ways you can do this; both directly and indirectly.
Firstly, if you are comfortable to, you might let her father know of your discovery and directly ask her him and his wife not to smoke in front of her any more to try and deter her from doing the same and set an example for her. Depending on their own attitude towards smoking will determine how receptive to they will be to this suggestion.
Alternatively, you can take the direct approach with her and inform her of the dangers of smoking. At her age, she is probably aware of the risks she is taking and the potential damage to her health that smoking can cause, but to make the message even stronger you can draw upon Islam and the fear of Allah to make her desire to stop more. If she is strong in faith then her fear of Allah might drive her to stop, especially given that many scholars even go as far as to say that smoking is haram.
Haram because of the damage that it does to the vessel that carries our soul. The vessel that Allah entrusted us with and therefore to smoke is to destroy what Allah entrusted her with and Allah will not be happy with that. You could either address it directly with her like this, or less directly, by being more open in your worship and developing a relationship with Allah. Praying together, reading Qur’an together or fasting together for example. Things that will bring you closer to Allah and make the fear of Him even more. This heightened consciousness of Allah could assist in the desire to give up in order to please Him. This way you don’t have to directly tell her to fear Allah and stop, but simply let this process happen naturally.
Smoking is an addictive habit, so if it is that she is already addicted, then you might support her in giving up, either by directly helping her to try methods to quit such as nicotine patches or gum, or to engage in other, more productive activities that can provide the same kind of hit that smoking does, for example exercise. You can support her with this by exercising with her, going out for regular walks together. This could serve a few different purposes. Firstly, she may get breathless quickly which will make her physically see and feel the damage the smoking is doing to her and give her the drive to stop. Additionally, exercise is a natural mood booster. One that can prevent the desire to pick up a cigarette. Furthermore, the time together will increase the bond between the 2 of you and give the opportunity to express your concerns about her smoking in a good space. A space where she might be more receptive to your message and concerns that she will be more willing to try.
Ultimately, it’s your choice how you want to address this issue, but there are a number of different routes you could take depending on the kind of person she is and which approach you feel she would be most responsive to.
May Allah make it easy for you to address this important issue with her and may He guide her to stop smoking.
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