"我应当去做点我自己的事，我应当这一辈子有点价值吧？" - The best thing she can do is to yield the job to young people who need to have a career and money for future and family later. So pleas do something good for young people and the society, please.
You can start working at any age in the U.S and find pretty good jobs with full benefits. Age isn't a problem here. And there's no reason to stay at home for 20 years. 3 is old enough for a child to go to daycare. There's nothing to do anymore at home after that. So 8 to 10 years for three kids is enough.
