This should be OK but unfortunately this is all up to the customs officer they see upon arrival back in the US. If they have a transit and don't leave the airport then this should not be an issue, whereas if they stay 2-3 days it may especially if they stayed exactly 180 days.
They will need to be prepared with a PRINTED copy of their ticket back to India which should help to allay issues related to overstay.
Their visa to visit US from India will normally be timed by date from entry to the US - typically 180 days - it would be better if they went to Canada earlier in their time in North America then returned to the US well within the time of the original visa stamp rather than near the end or certainly after it. Another option is going to Canada first then to US where the clock starts ticking on their visa time.
Originally Posted by
UA Fan
My in-laws will be spending six months here and on the return will visit Canada. When they leave Canada for India they might need to transit the US or stay 2-3 days at a connecting point. Relatives feel this is a bit risky as they would be re-entering the US after a long stay. Appears that there have been people who will just cross the border to Canada and come back for another 6 months.
Anything to worry about?