Kim Sarubbi and Carl Abramson, from Tennessee, have named their son Camden Sabr.
Sabr is a surname created by Kim and Carl, and is already used by their two older children, Alex and Maya. However, Alex and Maya were born and registered in other states, where the newly created surname was passed without objection.
In Tennessee, where the couple now live, the name has been banned.
Local state law dictates that a baby's last name has to be either the father's last name or a combination of both parents' surnames – a rule which Kim and Carl say is 'outdated' (and we're inclined to agree with them).
The couple are now suing the state over the issue.
"We had a lot of fun creating the name," Kim told local news. "It's about changing the law. It's an outdated law."
"Our first two children have Sabr. So to have two kids with one name, but we can't name the other one Sabr. It's just bizarre," Carl added.
State officials declined to comment to local news in America.
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