The McMahon Family

I started to work on my family tree about 6 years ago. So far a lot of what I have is because someone else put in the work to gather the information. I got lucky and conacted the right poeple and ended up with a windfall of information at least for one branch of my tree (my grandmother's maiden name was Boston). The other branches don't extend as far back or outwards since I have to do the work pulling the information together. I don't ever seem to have the time to work on my family tree as much as I would like to. I do always try to go once a year to Washington D.C. to the archives to look at census records and passenger lists.
My grandfather Matthew C. McMahon came from Ireland to America in 1930. My grandfather Matthew was the oldest of 6 kids. His family owned a farm in O'Callanhan's mills, a small town in county Clare of Ireland. I would appreciate any information on my grandfather's parents and his siblings.
My mom's family has been in Pennsylvania for a long time. Quite a few live near Wilkes-Barre (see Christopher Boston line). I have some detail about generations after my great-grandma Thelma Keller (my grandfather Freas Lord's mother) but nothing of her ancestors. I do know her parents were Charles Wilson Keller and Eliza Jane Hontz. My great-grandma Thelma was born 12/14/1901. She married Dana Frear Lord (born 10/31/1900) son of Stephen D. Lord and Ida Mae Fiske. Base on a story my grandfather told me about my great-great-grandfather Stephen he was part native american but I don't know for sure if this is true or how I can prove it one way or the other.
Any information on about any of these people listed here would be greatly appreciated. Thanks!
I'm also willing to share any information I have.