Question about Petitioned parents with a Tourist child?

I have a question..
my friend Carol’s parents are going to the US because Carol’s brother petitioned their parents. So they are going to America for good. The were approved already…
Carol has a multiple visa and was invited by her brother also for a special occasion/affair.
At first, the parents will go there alone and it was filled up in their DS230 form .
The question was :
1. who are you travelling with? of course the parents answered their respective names… the husband answered his wife and vice versa
2. Anyone following after?
they answered not applicable coz no one’s really following.
Now the DS230 and other requirements were already submitted..So the visa was approved and they were asked to go to America asap as according to the sched of departure..

Question :
Carol, the daughter was invited to attend an occasion in the States, so she arranged going to America together with her parents.
Will there be any conflict on this since the parents earlier stated that no other children is travelling with them? it was a last minute change w/c of course cannot be modified or edited on their DS230 since it was already forwarded..
Will this be a problem in the immigration once the plane landed US?
Thank you so much

Carol and her parents are entering the US on different visas. She on a B2 visa and them on an immigrant visa. It so happened that they were on the same plane to the US. Parents did not "lie" when they said that there were no children accompanying them as there is no other using the immigrant visa. There should not be any problem.

Tags: Asap, B2 Visa, Brother, Conflict, Ds230 Form, Friend Carol, Immigrant Visa, Immigration, Parents, Special Occasion, travelling, Visas