My parents came to the US 6 months ago, and they bought 6-month round flight tickets in China from April 15 to Oct. 15. when they first entered the Chicago port and showed the tickets to the immigration officer, he gave them Oct.12 as the date for staying. However, we did not pay much attention until Oct. 15 when they left. It seemed that they overstayed in the US for 3 days by mistake. Will it be a problem for their re-entry next time? Their visa has not expired yet, can they still use the visa?
Thanks for your help.