"Historically, children did not automatically get their fathers’ surnames, and customs vary in other parts of the world."

"In England, until the 18th century, surnames were fluid, and it was common for children to have their mother’s or grandmother’s last name.... In many Spanish-speaking countries, a child is given two last names, one from each parent.... More common in the United States is hyphenating.... Many parents said the logistics of having different names — like at school or when traveling — hadn’t been a big obstacle. For some, questions had been welcome.... 'It does seem to confuse some people, but I kind of love that about it.... It actually solidifies the decision even more, because I like that we are helping to normalize different naming conventions.' One longstanding way for parents to include the mother’s lineage is to give children her surname as a middle name...."

From "Why Parents Give Their Children a Last Name Other Than the Father’s/Some American parents have been breaking the patrilineal tradition for generations, but the number who do so remains small" (NYT).