In may of this year my fiancee was denied entry into Canada - We didn't have a return ticket, and the border agent wasn't satisfied that he could support himself financially while he was here (he had little cash in his wallet and they wouldn't allow him to withdraw cash from a bank machine to show that he does have money). We are attempting another visit in October, this time with a round trip ticket and funds in the form of Canadian currency and travelers checks (As well as other documents to show his ties to the US). However, when he attempted his visit in may, he was a Mexican national, not a US citizen, and his travel documents included a Mexican passport and his US alien registration card. This time he will be travelling on a US passport, as he is now a US citizen ( His interview and his oath were taken on August 8th). My question is will he still be facing additional questioning at the airport? Will the "flag" still show us as he is now travelling with a different passport and passport number? As well as a different name on the passport ( Mexican passports include the mothers maiden name, whereas US ones don't)? And if it does still show up, will it cause even more problems?