Parents Got visa But not coming in next 6 months?is there any problem?

[sgk1980]

Hi,
My parents got the visa , but they are not planning to come in next 6 months to USA?I heard that they should definitley travel in the first 6 months other wise immigration will make some problems like that? is that true?can anybody help us?

[immihelp]

There is no problem. They can visit any time before the visa expires.