NO! Hitting your son, or your daughter, or anyone else is called battery. Battery is a crime in all fifty states and in most other jurisdictions. It is generally chargeable as a felony. Some states carve out exceptions for "corporeal punishment" (i.e. spanking), but in general, it is neither legal, nor acceptable to go around hitting people, especially children, and doing so is an invitation for the department of children's services to visit you regularly.
Yes it is OK to spank, or use corporal punishment on your children (my son is a police officer and we have spoken about this MANY times) it is NOT OK to abuse or beat your children!
Your daughter's son is your other daughter's nephew and she is his aunt.
Your mother's son is you or your brother. Your mother's son's daughter is your daughter, or your niece. Your mother's son's daughter's mother is your wife, or your sister-in-law.
No, she does not have a son or a daughter.
Your daughter's son is your grandson and you are his grandparent.
Your daughter's daughter's son is your great grandson, and you are his great grandfather or great grandmother.
the daughter of your son/daughter
Your daughter's daughter is your grand daughter. Your sister's son's daughter's son is your sister's great grandson and your great great nephew. Your granddaughter and your great great nephew are second cousins, once removed ,to each other.
your son
You are the great aunt/uncle of your sister's son's daughter, and your sister's son's daughter is your great niece.
Son, Cary Son, Steve Son, David Daughter, Ashley Daughter, Christie Daughter, unknown
Your daughter is your sister's niece. Your daughter's son is her great nephew.