Jon Stewart returns in February as a once-a-week host for his old late-night program, The Daily Show. Stewart, whose original last name is Leibowitz, has often talked — and bitterly joked — about growing up Jewish. Among other things, he’s said he was taunted by kids who rhymed the “witz” in his last name with obscenities (“Leibo-t–tz” and “Leibo-sh–tz”). His stage name, Stewart, is a variant on his middle name, Stuart.

The comedian’s father, Don, walked out on the family when Stewart was a kid, and their relationship never recovered. But Stewart has always expressed love and admiration for his mom, Marian Leibowitz, who is 90. Here are five things to know about her.

1. She was a respected educator

Leibowitz worked as a public school teacher in New York City and later as an educational consultant in New Jersey, where Stewart and his brothers were raised. Leibowitz was often quoted in articles on curriculum development and related topics, including by The New York Times. Stewart sometimes mentioned her approach to education in interviews, at one point telling the Obama White House Domestic Affairs chief Melody Barnes: “The biggest complaint I hear from teachers — and by teachers, I mean, my mom: the teaching to the test.”

Leibowitz was president of the New Jersey Association of Learning Consultants and the state Association for Supervision and Curriculum Development. She also coordinated special education for the Education Improvement Center of Central New Jersey, with a special focus on gifted children. 

2. She wasn’t a stay-at-home mom

Stewart, 61, has said it was an “anomaly” to have a mother with a career when he was growing up in the 1960s, an era when many middle-class moms stayed home tending to the kids. “I couldn’t be more impressed by what she did in her life,” Stewart told one biographer. 

3. Family fortunes fell after the divorce

Stewart has said his mother “had a quiet confidence because she had to fend for herself” after his father left. His older brother Larry’s bar mitzvah took place at a fancy hotel, but by the time Jon turned 13, finances were tight. Stewart’s bar mitzvah was held at the Jewish Center of Princeton, a congregation a few miles from their home in Lawrenceville, New Jersey, in order “to keep the costs down,” Leibowitz has said. Leibowitz eventually remarried and had two more sons, Daniel and Matthew, with her second husband.

4. Stewart reminds his mom of her father

Leibowitz’s father, Nathan Laskin (Stewart’s grandfather), was born in China and grew up there in the small Jewish community of Tianjin. “Jon is most like my father,” Leibowitz said in a 2006 interview with The Times of Trenton. She described Laskin as being “very funny, and, when he was young, he made extra money entertaining in nightclubs in China,” performing for other Jewish merchants. Laskin emigrated to Seattle but eventually settled with his wife Fannie on the Lower East Side of Manhattan, where Marian lived as a child. Stewart was close to his grandfather, saying he loved the man to death — even though he described him as something of a bigot, “one of those lucky immigrants who got off the boat, signed in, and then turned to the people behind him and went, ‘Now get off my land.’”

5. She held her tongue on Stewart’s career plan

When Stewart “decided to become a comedian, it was a little bit of a shock,” Leibowitz told The Times of Trenton. “But he was going to New York. He wasn’t going to China. I decided I wasn’t going to be the person to discourage him.” Stewart’s father’s reaction was different, she told The New Yorker: “All Jon had ever done was host the high-school talent show, so his father said it was a ridiculous idea. I didn’t say it, but I figured, New York City is an hour and a half away, he’ll be back soon enough.”

As it turned out, she was wrong.