I hope you won't hate me for suggesting that you have records for two different people.
There are a number of different sources for the names in question:
Your grandfather's birth record.
Your grandfather's siblings' birth records.
Your grandfather's marriage record.
Your grandfather's siblings' marriage records.
Your grandfather's processetti records
Your grandfather's siblings' processetti records.
Your great-grandfather's marriage record.
Your great-grandfather's processetti.
Your great-grandfather's birth record.
Depending on the time frame and the commune, all of these might be available on microfilm at a Family History Center. In a case like this, I'd want to investigate as many of these as possible before dismissing an inconsistency as a "mistake" in the record. Working from the top of this list down, I suspect you will find a preponderance of the evidence suggesting where to look further.
In my experience, a discrepancy between a person's birth record and HIS OWN wedding record is very rare due to the documentation that is required a the time of the marriage. In other words, your great-grandfather would have had a copy of his own birth record at the time of his wedding (it is in the processetti) so a discrepancy is hard to fathom. Not impossible, but very unlikely.
[EDIT: Sorry, I didn't actually answer your question. There is nothing about these surnames that suggest a relationship. The Carmelo/Carmine thing is easy to see, but the surname swap is a puzzler.)
Are both these records from the same Comune in Italy?
Keep in the back of your mind that towns in Italy were generally populated by only a couple dozen surnames. It is very possible for there to have been a Carmine & a Carmello marrying two women named Antonina and each producing a son with the same given name born in very close proximity datewise. I would take the names on the marriage naturally as you know for certain this is your ancestor and his parents. Then look for another birth record where the parents do match the marriage. As the earlier poster stated, Italian Civil records are quite accurate. I have only seen mistakes in maiden names on the death records, where the informant made the error.
Carmelo & Carmine are not interchangeable (there is the slim possibility that he carried BOTH given names, but it is unlikely he would have been listed on one record as simply "Carmelo" and the other "Carmine", they would both be most likely listed)
badbatsmoru wrote:Got the birth and marriage certificate for great-grandpa. Last name for his mother on each document are so incredibly different (incidentally, she still has the same first name )
Antonina Groi Antonina Dipari
The writing is distinct and unmistakable. Anyone have an explanation? Are these names somehow related?
Also, great-grandpa's father is listed as Carmelo on the birth record and Carmine on the marriage certificate. Is one a nickname?
Hi: Carmine and Carmelo is same concept name, why boths coming from from Madonna apparitions: Madonna del(of) Carmelo also knowed as Madonna del (of)Carmine;
the second question is more difficult, why same person and two different surnames; so I think possible that or only 1 just and most probable only the surname that is on ancient certificate; or is possible that an surname really is mother's suranme.... suanj
I think the key to resolving the surname difference will be additional research. As Viveviz pointed out the names will be repeated in many documents. Sibling research can be vital to solving this. Also as you go through microflim watch for your ancestors name to appear that might really be a cousin.
But, mistakes can happen. Registars can be overworked or careless. Many represented in the documents could not read or write to verify what was written.
In one family I have researched extensively, I have found "errors" with names n the vital records. The surname was not common in the village, actually only belonged to two distict and unrelated families. As I went back through microfilm 1910 - 1820 I traced both families. They remained without a common ancestor and ultimately from two different villages. As the family trees completed there was no doubt where errors occured. In some records children were recorded with their christian name, figlio/a di Alfonso fu Salvatore. Others as christian name, figlio/a di Alfonso fu Michelangelo. It turned out Alfonso was the father, Salvatore the grandfather and Michelangelo the great grandfather. I can only guess the registar assumed he know the correct name of the father who reported the births. All the other birth, marriage and death records confirmed this.
So, continue your research. Be alert for "your" ancestors name to appear and it not be "your" ancestor. I think as you complete your microfilm research you wil be able to answer this question