My in-laws, who are Canadian citizen, came to visit me in US two weeks ago. At the border, they told custom officer that they plan to stay with me for 8 weeks. However, they are told that they can only stay in US for three weeks, because "they did not carry enough winter clothes to make it reasonable that they will stay here for 8 weeks". On their Canadian passport page, one of the page is stamped with admission date, along with a wierd handwritting "3/2" word along with the admission date. There is no other document/form that indicates that they must return to Canada by certain date.
Indeed, they did not bring a lot of clothes with them, so that they can carry just one small "carry-on" luggage to avoid the extra fee on airline.
My question: do they have to return to Canada in three weeks, or can they ignore the "order" and stay with us for 8 weeks, without any future negative consequence? Thanks.