When Holly is writing Gerry's parents' address on the packages to send to them in Ireland, she writes their names and then the address as: "412 Jerious Lane, Enniskerry, Ireland." The address was obviously Americanised as the Irish postal system requires the county to be written on the address as well, so, the address should have been written, "Enniskerry, Co. Wicklow, Ireland." Also, when Holly visits Gerry's parents, they live on a country road, and in Ireland, the country houses are not numbered and the country roads do not have names. There are small regions called townlands instead.
[First, leaving the county off the package would be an easy mistake for an American to make, And yet, the package would likely find it's way to the proper address without it. The home we see may not be where the parents physically get their mail (especially if un-numbered on an un-named road), so the address she used may be where their mail is indeed picked up.]
Corrected by John W Rosa
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