In the event that you've got a lot of time on your hands, you'll want to make sure that you've got a good idea of what you're getting yourself into. Starting from not having responsibility, the problem will spread to everything, especially one of our closest members, for example, it is not uncommon to find gamblers who like to borrow money from one of their relatives who eventually cause problems because of the inability to pay debts due to excessive gambling and even though they have money but of course the first thing they think about is to fund their gambling and not to pay debts.
Not only that, the scenario can also be like what you said where the point of view of the surrounding community will be bad as a result of the behavior of an addicted gambler who usually ranks like a madman and agreif, acting out of control and even very likely to commit crimes such as stealing etc., which of course can embarrass their extended family in the eyes of the surrounding people. I think there should be something that one of his siblings should do to at least advise him not to overdo the gambling, although the possibility is small but it doesn't matter as long as it is consistent I think it can make them change a little.
I've noticed that it's rare not to have in a family a person who acts in a strange manner. It could be as a result of childhood upbringing. Which may have affected the person psychologically. Home training changes people differently. Grown ups hardly find it difficult to change, once the person gets addicted it takes lots of effort to cure their problem gambling. Even after the problem has been solved the gambler would find himself undergoing similar gambling symptoms for a while until he's completely in control of his actions. Advising them helps, but not everyone loves to take one, especially when they didn't ask for it. As families we only need to have to closely observe the person and endeavor he's not gambling all the time. Explaining to them that gambling once a day is achievable can help the gambler would decide to try it out some day. Then he'd follow the routine of gambling once a day for a long time till it's now a part of him.
Yes, regarding the nature and behavior, it is true as you said that usually such behavior starts from the parents' mistakes in educating their children when they were young, simply put, if their parents educate them harshly or mean to treat them harshly since childhood, then usually when they grow up they have traits and behaviors not much different from what their parents taught them, But for this problem I really can't make it a benchmark for someone to then enter addiction when they grow up, because I think what makes more sense is the wrong environmental factors that can really make someone involved in gambling until they enter the addiction phase or other negative things.
The environment has a very big influence on a person's behavior and changes in any case, it can lead to positive or negative things and usually the environment when they are older is where all these situations and scenarios can start, on the other hand basically it is not an easy thing to get out of gambling or even the addiction zone, because there are so many temptations that are difficult to miss by them and as you said that although there are many suggestions that are so good but not everyone can accept them into consideration. Therefore, the conclusion is that the action to cure gambling addiction must come out of themselves, or that means it cannot be forced and will really be successful or likely if there is basically a firm intention and sincerity from someone who is already addicted to recover.