Hope this finds you well, and helps you somewhat...I believe my paternal grandfather Antonio Ricciardi was your great-grandmother Maria's brother -- altho the records I have for him all give a birthdate of July 2, 1895. He was born in Airola, in the province of Benevenuto, Italy, and DID have a sister Maria Pasqua (or Mary). His parents were Gioacchino Ricciardi (1851-1921) and Maddalena Iuliucci (1864-??); he immigrated to the US in 1912 and married Maria (Mary) Buscemi in 1921, and lived in Boston, Fitchburg and eventually Watertown, MA. Antonio (Anthony) died in 1987. His other siblings included Dominic, Gabriel, Antoinette and Immaculada. He had four children, including his second son Joseph (Joe), who passed away in 2005 -- my dad.
If any of this sounds similar to anything else you have, let me know and I'd be glad to share whatever else I have or find with you -- I have some other records of my grandfather's parents and grandparents that might help!