When the show premiered, Ann Romano was a single mom taking care of her two daughters. Mackenzie Phillips played older daughter Julie, while Valerie Bertinelli played younger daughter Barbara.

Dwayne Schneider, who is commonly referred to by his last name, works as the building superintendent at the apartment building where the family lives. Over time, he becomes a true friend to Ann and her girls.

Mackenzie Phillips, who played big sister Julie, struggled for years with substance abuse. Producers fired her from the show in 1980. She was brought back briefly the next year, but written out for good after she relapsed.

Ann was a PR professional and worked for a firm called Connors and Davenport throughout much of the series.

Julie had big plans to marry med student Fred in season five, but she found herself pursued by Fred's best man, Max Horvath. She finally decided against marrying Fred and became Mrs. Horvath instead.

Julie is all set to fly out to California and have an all-natural water birth. Instead, the baby comes early and she gives birth in the bathtub at her mom's apartment. She and Max name the baby Annie, after her mom.

Ann finds herself annoyed with an artist named Nick in a two-part story arc in season six. She later dates Nick and helps care for his son Alex.

Ann and her husband Ed had recently divorced when the show premiered, but Ed is alive and kicking. He later remarries a woman named Vickie, which frustrates his daughters, who feel he is neglecting them.

David Kane was Ann's divorce attorney and neighbor. He later develops feelings for her, but Ann is happier with a platonic relationship.

Ann's struggles as a single mom begin in the very first episode of the series. Julie demands permission to go on a coed camping trip with her friends. If her mom says no, Julie threatens to move in with her dad.

Julie is dating Chuck when the pair run away in the season four premiere, leaving Ann frantic to find her daughter after a fight about Julie's future. Schneider gets in on the act, trying to track Julie down using his CB radio.

After Ann turns downs his earlier proposal, David returns from a trip to Los Angeles in season two to ask Ann once again for her hand in marriage. While her daughters encourage her to accept, Ann finally decides that she is just not ready to remarry.

Julie crashes her car into Dr. Paul Curran's car. Determined to pay for the damage by herself, Julie takes a job in Paul's veterinary office. The pair eventually fall in love, even though Paul is more than 20 years older than Julie.

Schneider is excited when a genuine celebrity moves into the apartment building -- race car driver Cam Randolph. While Julie and Barbara are excited to set their mom up with Cam, Ann eventually decides he's just not right for her.

Julie is thrilled to get her own place in the season three two-part premiere episode, "Julie's Big Move." Ann is more than a little concerned when she learns that Julie's new roommate does favors for rich men in exchange for money.

Ann meets sports writer Mark while visiting a doctor about her sore shoulder. She falls hard for Mark in the season four premiere, but later finds out that he's already married.

Nick is killed in a crash with a drunk driver in the season seven premiere. His son Alex moves home to Chicago to live with his mom, but eventually returns to Indianapolis to live with Ann and her daughters.

Needing help to keep the business going, Ann partnered up with former rival Francine Webster. Schneider later makes them a business loan so they can grow the company, after they are turned down by the bank.

Barbara gets engaged to dental student Mark Royer in season seven. While on a conference to Vegas, they decide to elope -- but later change their minds and conclude that they want a big wedding with family and friends.

Mark and Barbara's wedding took place during a two-part episode at the start of season eight. Unfortunately, Mark was nearly late for the ceremony after sneaking out to participate in a golf tournament on the morning of the wedding.

When Ann finally decides it's time to get married to Sam, during season eight, the pair go to a ski resort on their honeymoon. Unfortunately, Sam gets injured on the slopes and spends most of the trip recovering.

With her daughters grown up, with families of their own, Ann decides it's time to leave Indianapolis and move to London to take advantage of a new job opportunity.

As Ann moves to London, Schneider learns that his brother has been killed. He moves to Florida to take care if his niece and nephew -- which means he finally has a family of his own.

It may be one of Norman Lear's lesser-known series, but it's also one of his longest-running shows. "One Day at a Time" ran for 209 episodes over nine seasons, from 1975 to 1984.

The 2017 reboot of the show on Netflix features many of the same themes as the original "One Day at a Time," but focuses heavily on the characters' Cuban-American heritage. Justina Machado plays single mom Penelope Alvarez, the star of the series.

In the remake of the show, mom Penelope is a former Army member who served in Afghanistan. When she leaves the Army for civilian life, she takes a job as a nurse for boss Dr. Leslie Berkowitz.

Penelope is proud mom to two children -- just like on the original series. They include daughter Elena, who comes out as a lesbian, and son Alex.

The Alvarez family includes three generations living in the same household, with Penelope's mom, Lydia, living there to help care for her grandkids.

Dwayne Schneider was so much more than a handyman in the original series, so it's no surprise that he was brought back -- with the same name -- in the reboot. In the new version of the show, Schneider's wealthy parents own the building where Penelope and her children live. He's no handyman, but he does help out from time to time and he is a true friend to the family.

In traditional Latin American culture, a quinceanera is a big deal for girls, celebrating their coming of age on their 15th birthday. Elena is reluctant to go through such an ordeal, but her mom has her heart set on a big celebration.