Dear Mary, Good to hear from you. I cannot provide speciific information on your family since my family spelled the name Mahar. The Maher's, like your family, were in Tipperary county and spelled the name interchangeably with Meagher. I have seen other spellings for Maher like "Mayher" in Canada but usually it is spelled Maher or Meagher. The name was in a state of change in the 16th, 17th and 18th century and originally the clan was Tipperary born(Ikkerin) and O'Meachair an ancient obsolete gaelic word meaning amicable. Beginning in the middle 18th century the name was spelled Maher and to a lesser extent Mahar. It seems, after the Cromwell land dispersion, many left Tipperary County to probably Belfast or Dublin where they would have the best chance of survival. These clan wanderers took names like Maha, Mahaw, Marhar and Mahar which became the most prevalent form of the name outside of Tipperary. The name Maher, or Meagher which is about 100 yrs older than Maher, always was found in Tipperary. What you have is a large generation gap between Mahar and Maher after about 1660. My family was here well before the start of this country since Edmund Mahar (spelled in census sometimes Marhar, Mahaw)came over either with Capt. Robert Owen or(either or both) the army of Gen. James Wolfe during the French and Indian War. Edmund settled Pembroke, Maine in Washington County and had a colorful life. Where he came from I do not know. Your family came over after the Potato famime and you know they were from Tipperary County. In 1850 their were 220 Mahar families and 328 Maher families and maybe 8 Meagher families in the US. Both Mahar and Maher settled in New York State in large numbers initially. I would say 40% lived in this state. Most of the Maher's, for some reason stayed around New York City, whereas, the Mahars, moved to the vicinity of Albany County. For some reason the largest concentration of Mahar's , even to this day, is around Albany. Some Maher's lived in Albany but not many.Another large concentration of Mahar's is Maine but they are mostly the descendents of Edmund Mahar. The Maher's and Mahars didn't seem to live in the same area even in this country. Why that happened I don't know. Maher is the most prevalent spelling.What I said before is just what happened and I can't explain it. I doubt if someone would have changed from Maher to Mahar or vice versa. Some may have reverted to Meagher and Edmund Mahar sometimes is known as Edmund Meagher or more precisely Eamonn Meagher.