No, probably Helena changed her name to sound more American, Helen.  That was the whole family.  The parents were born around 1880, got married the normal time, in their early 20's and immediately started having kids from 1903-1908.  The 1920 census is the one that had all their kids because the kids were still under 18.  The kids weren't born in the US, but since they were young when they came, would have acted more American than Dutch, except for the things they learned from their parents.  And also, there being a lot of immigrants in the US at that time, customs were a lot different back then.  But, two of the girls had been divorced and the guys had not married even into their 20's, which is probably not what the Dutch do, but probably more common in the US in the 20's and 30's.  Because the normal for a lot of cultures back then and even some places today is to marry and have 4 or 5 children or more young, and stay married, just as Peter and Marie did.  They were taught to stay with their spouses even if they have problems.  I just imagine that Peter and Marie had problems by knowing the kids getting divorced, and not getting married, and becoming alcoholics and getting sick, and things like that.  But, also medicine wasn't what it is today in the case of some illnesses, and maybe dad's dad didn't become an alcoholic because of what his dad did, or he could have started drinking after his dad died, since we know he lived with his parents in his 20's, at least up until his dad died.  There is no real way to know these things, what happened in their household.  But we just have a general idea of things, by the records we have.  California was also a very liberal place even back then, and that affects things people do and attitudes people have about life.