CHICAGO (CBS) — Who do you look like? Where’d you get your sense of humor? If you were adopted, you may not know.

But as CBS 2’s Roseanne Tellez reports, a new Illinois law is giving thousands of adoptees a chance to find answers to those questions.

READ MORE: Chicago Weather: Rain Saturday Ahead Of Chilly Mother's Day

Beginning Tuesday, adult adoptees can apply for a copy of their original birth certificate.

LISTEN: WBBM Newsradio’s John Waelti reports

Donna Haag, who grew up in a loving adoptive family, already learned her biological parents have died, but also that she has a sibling. Getting her birth certificate means she’ll now have the key information – her parents’ first and last names — to try to find them.

“If there’s any information about an older sibling, I’d love to find out,” she says.

Adoptees have always found ways to search for a parent. David Wywialowski was able to forward a letter to his birth mom, through the agency that handled his adoption, Catholic charities.

He treasures her written response, the first contact he had with a blood relative. But she declined to meet him.

READ MORE: Mayor Lightfoot Delays General Iron Permit To Move To South Side Over EPA Concerns

“That was just totally amazing,” Wywialowski says. “This was now my first contact with a blood relative.”

But she declined to meet him.

“There’s a whole mixed bag of ways that it can turn out. Do not go into it a reunion with too many expectations.

While Wywialowski did track down his father, it was too late for a meeting. He had died, leaving behind two sons – David’s half-brothers. He found them.

“These connections were really amazing to me and blew me away,” he says.

A lot of adoptees are more interested in learning medical histories than connecting with relatives. And some just want a birth certificate, the paper that the rest of us may take for granted.

MORE NEWS: Chicago Night Clubs Gear Up For Looser COVID-19 Restrictions As State Prepares To Enter Bridge Phase

Biological parents who want to remain anonymous may have identifying information deleted from those birth certificates. For more information about the new law, click here.