Philadelphia father uses cheesesteaks to measure infant son every month for a year

— -- A Philadelphia father has started a unique family tradition that involves cheesesteaks -- but not eating them.

Instead, Brad Williams uses the sandwich to measure his son, Lucas Royce Williams.

The tradition started in 2015 when Williams bought cheesesteaks for dinner shortly after Lucas was born.

“I realized the cheesesteak was a pretty close size to my son,” said Williams, whose son Lucas was 2 weeks old at the time.

Williams took a picture of his son with the cheesesteak, and shared it on Facebook with friends and family.

“[The photo] got a good reaction on Facebook, so I decided to make it a monthly tradition,” Williams told ABC News.

Every month for a year, Williams made sure to get a cheesesteak for dinner.

“We usually ordered from Dalessandro’s, but sometimes we’d go to closer cheesesteak places for convenience,” said Williams.

According to Williams, he stopped taking pictures after a year because Lucas was getting tired of cheesesteaks. Williams recently posted the year of photos to his personal website, calling the photo collection "Cheesesteak for Scale."

Lucas is an only child, but if he gets a sibling, Williams says they will be continuing the cheesesteak tradition.

Said Williams, “It’s fun and it puts a smile on people’s faces. Plus it’s a reason to eat cheesesteaks every month.”