FitzGerald, Leonard, O"Sullivan & Sheehan

Hello, one & all, pleased to "meet" you! Hope you & yours are well? I've been helped before, let's see if anyone can help me mote? I have found it difficult doing Iriah research from this side of the Atlantic, I live in Worcester, MA, USA. What I have is Mary Katherine Sheehan born May 1887 (what day exactly?) Ballymacthomas, Cork City, Co. Cork, Ireland, she & her parents, John J. Sheehan & Helena FitzGerald came to America between then & her next siblings birth in 1889 in Peabody, MA, USA. Now is Ballymacthomas a street address, a parish,, or what? Is what ship they came over on possible to find? If anyone else of their family came w/them & the date of their departure & where they arrived at NYC, Boston, or Canada (double boaters?) If they left from Cobh,, or somewhere else, when they left?  Now  John J. Sheehan & Helena FitzGerald were married in May 1884 (What exact day? Where?) On the marriage cert. it gives both of the Father' given names as John, w/John Sheehan being dead by the time of the marriage, thus before Aug. 1884? (what exact day? He is said to have died in the Cork Workhouse? Is that true & of what? His wife was Mary Maher (?), is that correct(?) when & where did she die? Did John & Mary have any other kids?  Did they remain in Irelaand or immigrate too? John Sheehan was a Labourer? His son, John J. was a Tailor? Now as to John FitzGerald, did he have a middle name? He was a Baker in Cork City? (There's a FitzGerald Bakery in Cork, City or County, not sure which? Did he have anything to do w/it? He was married to Jane Anne Leonard, where, when & her line? Jane Anne Leonard FitzGerald died of Dropsy. He then moved in w/another daughter, Mary FitzGerald O'Driscoll, wife of Thomas O'Driscoll, where in Cork City was that? He lived there, w/them until his death in 1908. When exactly did he die? Was it in their home or a hospital? Details about the other O'Driscoll family members? Names, dates, locs.? Was this John (middle name?) FitzGerald, the son of another John (full name?0 FitzGerald & Mary O'Sullivan? Her parents? Siblings?  Helena FitzGerald Sheehan & Mary FitzGerald O'Driscoll had a brother who came to America as well, Jeremiah J. FitzGerald, here he married Mary Jane McDarthy & they had children! Any chance anyone knows anything about them? Thank you in advance for any help! I realize that it's a lot to read, but wanted to give as much info. as I already had!. Be well, Jack MacDonald-Hilton now from Worcester, MA, raised in Danvers, MA, proud descendant of Capt. Amos Hilton, originally from Manchester, MA, Founder/Settler of Yarmouth, NS, Canada.