There is much of life that is random. I think first that where we are born may give us a good start or not. I was fortunate to be born in an affluent country. I didn't experience hardship as a child and had the security of loving parents. We weren't rich, but we weren't needy. I also was fortunate to have a mother who helped others, whether helping with resettlement of displaced persons or health and education services for migrant farm workers. Hearing their stories taught me how fortunate I was indeed.
My children didn't have the luxury of love and security for the first few years of their lives, which were spent in an orphanage. My older child constantly worries that this period of security with me will come to an end and he will be alone again. My younger child seems to accept that she has a forever family, and that things will work out well for her. I wonder how much of the difference between them is due to innate personality differences and how much is due to their early experiences.
Last weekend, I listened to a radio program about happiness. Happiness, it was said is 50% genetic, 10% environmental, and 40% due to personal choices, especially in relationships, and trying to help others. Even the environmental seems only to be an issue if there is true hardship and loss, and so is not proportional to income. This certainly seems to be the case. I have met very many poor people who seem happy and rich people who don't. As the saying goes, "Money can't buy happiness."
I do think that a portion is intrinsic, whether genetic or not, I can't say. Some people certainly seem more able to find happiness than others and even seem to make those around them happy. I am fortunate there, too, in that my mother was one of those people. My younger child is as well. I'm trying to help my older child find that much of happiness is within himself.
The last part is due to personal choices. I agree that seeking money or prestige doesn't help to achieve happiness. Happiness has to be in relationship to helping others. This seems obvious when I see my older child helping the younger to learn a new skill. He seems happy then. And he is a good teacher. I hope that with time he learns to value that more in himself.