In addition to those people who became Canadian citizens upon the coming into force of the Act (popularly known as the “1947 Act” due to the year it came into force), citizenship afterwards was generally acquired as follows:
.... grant of citizenship to a foreign woman married to a Canadian man after one year’s residence as a landed immigrant....
Hoo boy. So Mrs Cruz could have or would have become a Canadian citizen in 1969, since Cruz Sr became one in 1968. So if that is accurate, then Cruz Jr was born in Canada to two Canadian citizens. If those were the circumantances, he would not have any claim to any kind of US citizenship at all, unless he becames naturalized at some point.
So Mrs Cruz would have had to go through an application process to become a Canadian citizen, I would assume.
Wikipedia is the easiest reference to the information or http://www.theinfolist.com/php/SummaryGet.php?FindGo=history_of_canadian_nationality_law
Acquisition and loss of citizenship under the Act
In addition to those people who became Canadian citizens upon the coming into force of the Act (popularly known as the “1947 Act” due to the year it came into force), citizenship afterwards was generally acquired as follows:
A. birth in Canada (except where neither parent is a citizen or permanent resident and either parent is a representative of a foreign government, their employee, or anyone granted diplomatic privileges or immunities)
B.Naturalization in Canada after five years’ residence as a landed immigrant
C. Grant of citizenship to a foreign woman married to a Canadian man after one year’s residence as a landed immigrant
D. Grant of citizenship to women who lost British subject status prior to 1947 upon marriage to a foreign man or his subsequent naturalization
E. Registration of a child born outside Canada to a Canadian “responsible parent” (being the father, if the child was born in wedlock, or the mother, if the child was born out of wedlock and was residing with the mother, if the father was deceased or if custody of the child had been awarded to the mother by court order)
It appears that the naturalization under these terms was proforma for Ms Cruz and it ties in with her being on the voting rolls.