I am a US citizen and my mother is a Canadian citizen. I applied for her earlier this year. Just now received a letter from UCIS regarding her I-485. They are asking for evidence of inspection, admission into United States, such as I-94, Visa. My mother entered US by land. US Customs and Border Patrol doesn't issue any I-94 or stamp the passport. They don't even record the arrival. There is no record. Anyone had a similar experience? Should I just send them a letter explaining why my mother doesn't have a arrival record. Any answer or suggestion will be greatly appreciated. Thanks.