It is very important for us to be very observant and watch well before we take decisions even when we are doing what is giving us money. We need to keep our gambling lifestyle secret from our children and family so that they will not follow that path since they might not be aware of the risks that is involved if they don't control the way they gamble. Gambling can easily influence people around us if they noticed that we keep making consistent profits from it which is what everyone of us want to be seeing. This alone can attract non gamblers to start seeing reasons to gambler.
I could understand hiding that fact you gamble to kids and young people, as they learn by imitation and if they saw you gamble they may try it when they are nowhere near as mature to take that decision in a responsible way.
However I really think at least one of your family members should know about it as a form of fail-safe, after all even if you believe you will never get addicted, it is impossible for you to be sure about this 100%, and if no one knows what you are doing your addiction could proceed unimpeded, but if another family member knows what you are doing they could realize what is going on and get you some early help.