No, you can't get citizenship from a great-grandparent
	like that.  You get citizenship from your parent at the
	time of your birth (see the Nationality and Citizenship
	Act,section six, subsection two).  If your parent was
	not an Irish citizen when you were born, you cannot get
	citizenship from him or her later.  (Obviously, this doesn't
	stop you from getting citizenship if you are entitled to it
	for some other reason.)  I emphasize: none of what is said
	here about citizenship is legal advice.  I could be wrong.
	Read the Act yourself, but if you want legal advice for
	your situation you will most likely have to pay a lawyer.

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