Retirement tax questions

I’m not sure why I can link the consumerreports link but not the marrotaonmoney link.

 

So what you’re saying is if the child earns $1500 a year.  Parent or grandparent can put $1500 into the custodial Roth IRA.  Child can keep the $1500 that he worked hard to earn but cannot add another $1500 into their custodial Roth IRA because the parent or grandparent already contributed?