I think they must be the same family. There seems to be a lot in common. For Lucy Agnes and siblings I have some names and dates. Joseph William 1867, Mary Jane 1863, Lucy Agnes 1866, Patrick 1869, James 1870, and John 1877. They were all born in Mullingar. By tradition the first son would be called after the paternal grandfather, in this case Michael, so almost certainly there was another, older, son. I am going to try to email you direct, it will speed things up a bit. By the way where are you based?