The one in Beverly is the original and very old school.
The original was on 79th street. It relocated to 95th street but approx 1/2 a mile east of the current location.
The first 95th street location had a wonderful long, red "beef burgers" sign that stretched into the sky. New landlords genericized the retail facades and ordered the brothers to take down their sign. Which they did a few months before moving west to the current location.
As their kids got older one of the owners, Bill, wanted to set up the next generation and expanded to Oak Lawn. And I think Orland. One of the cooks left and opened a knock off in Evergreen Park which eventually closed.
But the "top notch" named joints are all Soulian family owned and make the burgers, fries and shakes the same way.