Some say kin, others "family," or "relatives." Call them what you will, but you’re stuck with those people related to you by blood or marriage.
When someone refers to their kith and kin, she means her friends and family. Both words date back to Old English, kin reaching back to the 700s. Originally referring to one’s family or race, kin narrowed to refer just to one’s blood relations. Your "next of kin" is your closest family member: spouse, child, parent, or sibling.