Their children, all born here, went to school and worked all their lives. And all their sons (7 + 2) are/were WWII vets.
They came here legally, and it sounds like they became Americans whether they became legal citizens or not. I am sure they did not expect this country to change for them, they wanted to be a part of this country.
If I decide to move to another country I would not expect them to do things my way, or speak my language. I would expect to learn their language and adapt to their traditions and customs.
We have so many immigrants now, both legal and illegal that want to bring their country with them, which is fine for their own family traditions but they should not expect the rest of us to adapt to their ways. They should also expect to learn English as soon as possible, not expect us to learn their language.
When I was a kid I had a number of neighbors who spoke Italian at home. Mainly because either their parents or grandparents had immigrated and never became fully fluent in English. But they did their best when speaking with the rest of us. And their kids absolutely mastered and used English.
They were true Americans even without the language. I am certain they did not insist that American culture be changed to accommodate their customs from the old country.