Updated 07/24/13 – 1:45 p.m.

CHICAGO (CBS) — State Rep. Deb Mell (D-Chicago) was sworn in Wednesday as the next alderman of the city’s 33rd Ward, replacing her father, longtime Ald. Dick Mell, who is retiring after 38 years on the City Council.

Dick Mell announced his retirement earlier this month, and Wednesday’s council meeting was his last, as his daughter was formally sworn in just hours after Mayor Rahm Emanuel announced he was appointing Deb Mell as her father’s successor.

Deb Mell has been a state representative since 2009, and becomes the Chicago City Council’s first openly lesbian alderman. She was among a dozen candidates to take her father’s seat on the City Council, and was considered the heavy favorite for the job.

“I know there are some critics out there, and I’ve heard one … just a couple minutes ago, and that just makes me work even harder, and I have something to prove. You will not question my passion and my hard work on behalf of the 33rd Ward,” she said on the council floor after being sworn in. “I think my father probably speaks a little longer than I do, so I suspect our council meetings are going to be a little shorter.”

Stepping down after nearly four decades in office, Dick Mell said it simply was time for him to go.

“Time has passed me by. I don’t tweet, I don’t have Facebook,” the elder Mell said.

Although selecting any other applicant to replace Dick Mell would have been a major surprise, Emanuel said he picked Deb Mell for the seat for more than just her name, saying she fought on behalf of struggling families during the foreclosure crisis.

The mayor also lauded her for her work chairing the House Transportation Committee during a hearing into allegations of patronage hiring at Metra. Mell chaired a hearing that prompted Metra to release a memo from former CEO Alex Clifford, detailing patronage allegations against House Speaker Michael Madigan (D-Chicago) and others.

Emanuel noted Deb Mell won her first term in the House with 75 percent of the vote, and her third term with 82 percent. She won her second term unopposed.

“Others will say what they will, but while it would not be fair to appoint Deb just because her last name was Mell, it would have been equally unfair to her constituents, and the city, to refuse to appoint her because her last name was Mell. She should be judged on the facts,” Emanuel added.

Mell, who was diagnosed with breast cancer last year, has long pushed for same-sex marriage in Illinois. She married her partner, Christin Baker, in Iowa two years ago.

She has served as a state representative on the Northwest Side, including parts of the 33rd Ward, since 2009.

“I love this area, I grew up here, I learned how to ride a bike on these streets, drive a car on these streets, and I could not be happier right now,” she said at a Wednesday morning press conference at Horner Park, where she played Little League baseball.

Her sister, Patti Blagojevich — who is married to disgraced former Gov. Rod Blagojevich — praised Mell as she visited City Hall for her father’s farewell, and her sister’s swearing-in.

“She’s grown up in the ward, lived in the ward. It’s in her soul, the 33rd Ward, and she … grew up with my dad as a great example of constituent service, and serving the public, and I think she’s going to carry on in that tradition of the people first,” she said.

Deb Mell will serve out the remainder of her father’s term on the City Council, ending in 2015.

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