How do you spell SHEA, SHAY, ...?

Our family of proud "Shea's" were briefly distressed when in 1990 my grandfather applied for a US Passport and was told no Passport would be issued because "he did not exist" (at least this is the phrase I heard my mother use over the phone when communicating the problem with family). The problem being that my grandfather had grown up spelling his name Shea, had named all of his children Shea when his own birth record spelled his name "Shay." In fact, it seems, there was at least one more generation of name confusion before my grandfather.

Quinlan Shea (my great great grandfather) had five children, in their baptismal records from the church 3 of the five are spelled Shea and the other 2 spelled Shay. John, my great grandfather's, baptismal name was "Shay" as was the name on his city Birth Record. However by the time John was married he was using the spelling Shea as had been used by the family when they first arrived. The family has been heard to blame the clerks for noting the name incorrectly, but it is also possible that one time the family didn't know how to spell the name.

Has your family had spelling issues, how do you spell Shea?