One possible romantic resolution for a single parent is to marry the nanny. Or the governess. Or the Kindly Housekeeper, if she's younger. Or in general, anyone privately hired to care for the kids or the house. Writers abhor single parents, it seems, and marrying them to people who already act as Parental Substitutes to their children is the neatest way of fixing this.
Unless said nanny is secretly a Babysitter from Hell, the children usually do not object to this like they do with other love interests of their parents. They might even be the ones who try to make it happen in the first place. This is because said nanny already has their love and trust; making them the legal parent is just icing on the cake. On the parents' end, seeing how good said nanny is with their kids might exacerbate the attraction to them, especially if the nanny fixes the family's issues.
A Temporary Love Interest might get involved to make either side realize they share more than a mutual love for the children.
Compare to Teacher/Parent Romance. Generally falls under the first type ("child approves of the relationship") of Parent with New Paramour. It's also an inversion of Single Parents Are Undesirable. Since this is an employee/employer relationship, subtrope of Unequal Pairing. See also Magical Nanny.
- Love So Life: Seiji (who has custody of his young niece and nephew) eventually falls in love with their babysitter Shiharu, who reciprocates. This relationship is further complicated by the fact that Shiharu is only in high school.
- Defied in Ali Wong's standup special Hard-Knock Wife: She hired an elderly lady to nanny for her and her husband, because a hiring a "25-year-old pretty young thing" is a surefire way to destroy your marriage.
- In the Miraculous Ladybug AU Fic Second Chances by TheNovelArtist, Adrien, as a single father, has trouble finding a nanny for his daughter until Alya recommends him Marinette. Since she is recently widowed herself, it takes them twenty chapters to have a proper date.
- In the Harry Potter fanfiction Daddy's Boy, the recently widowed James Potter hires a nanny named Eloise (Liz). They fall in love but James has trouble letting go of the memory of his deceased wife. After a bit of matchmaking, he confesses his love for her.
- Strained Harmony has Setsuna proposing to the nanny she hired for Hotaru, Ranma, after a courtship with shades of Wife Husbandry, as Setsuna has spent quite a bit of Ranmas employment grinding away Ranmas social ineptitude and Raised by Wolves tendencies.
- In Addams Family Values, Fester is conned into marrying Black Widow Debbie, who arranged for herself to be the nanny to Wednesday and Pugsley. When mentioning it to the rich kids at summer camp, Amanda is absolutely disgusted by a rich person marrying "the help".
- In Au Pair, two children successfully scheme to set up their single father with their au pair (a type of nanny).
- The Beautician and the Beast: Joy is mistakenly hired to be a tutor for the children of Boris, the dictator of a Ruritania. They eventually fall in love.
- In Corrina, Corrina, the titular character, played by Whoopi Goldberg, is hired to nanny Manny's daughter Molly. Manny and Corrina find that they are compatible and strike up a relationship.
- The Hallmark film The Nanny Express is about two children who have driven away all their nannies, but meet their match when their father takes a liking to the newest one.
- In Nanny McPhee it's the scullery maid that Mr. Brown marries. Evangeline did settle fights between the children and took the time to listen to them before the nanny got there.
- The Rebound sees divorcee Sally fall in love with Aram, her children's much younger babysitter.
- In Jane Eyre, the title character is initially hired as a governess by the man she eventually marries.
- Agatha Christie:
- In The Moving Finger, it's revealed that Mr Symmington has been secretly in love with his beautiful nursery governess Elsie Holland, and that he killed his wife in order to marry her.
- A squickier variation in Ordeal by Innocence, where one of the children seduces the nanny (once he's in his twenties). He always was a vicious manipulative sociopath, getting the nanny to murder his adoptive mother... unfortunately, the nanny discovered she was the Secret Other Family when his actual wife came calling, so she stayed silent, ensuring he died in prison (by sheer coincidence, the man's alibi was unable to provide evidence at the trial).
- Vera Claythorne, a former governess from And Then There Were None, tried to invoke this by deliberately letting a young boy in her care die. The boy's uncle, Hugo, was in love with her but would not marry her since he was poor. The boy's death granted him the entire family estate, which would solve that problem... except he immediately realized the truth and broke up with her.
- In the Sherlock Holmes story "The Adventure of the Solitary Cyclist", the young lady who seeks Holmes' help was hired by Mr. Carruthers, a rich widower, to be a live-in music teacher for his daughter. He eventually proposes to her but she declines since she has no romantic feelings for him and is already engaged. Carruthers turns out to have been part of a scam to inherit Violet's fortune, but he fell In Love with the Mark and comes to her rescue near the end.
- Simon's Papa: Simon's problems with the other boys and adoption of Phillip as a father figure introduce the blacksmith to his mother, and they end up engaged by the end of the story.
- In "A Tale of Heroes," a Tarma & Kethry short story in the Heralds of Valdemar series, the pair rescues an inn's chambermaid, Fallan, from her abusive employer and take her with them. She proves to be absolutely hopeless at road life, alienating the two after three days. Fortunately, earlier in the story they guested with Landry, a widower farmer with five children, who had wished for someone to help with the children and house. Fallan proves to be such a perfect fit for the household that after a week, both Tarma and Kethry can see that Landry is already thinking about proposing.
- The Yulianna series by Yulia Voznesenskaya concludes with Dmitry Mishin deciding to marry Alexandra, his daughters' governess (appointed, ironically, by his previous Gold Digger fiancee). The girls are enthusiastic about it and actively ship them, though they consider Alexandra to be a Cool Big Sis rather than a Parental Substitute, since she is much younger than their father and their late mother.
- American Gods. Essie MacGowan is hired as a wet nurse for the child of a wealthy man whose wife died in childbirth. Eventually she seduces him and they get married.
- Played for Drama in the episode "Nanny McDead". Sara, the titular dead nanny, was suspected of having an affair with her employer. It turned out that she and her fellow nanny Chloe were having affairs with the same man — Chloe's employer.
- In another episode the victim was killed by his stepmother and former nanny who had done it because he had come close to realising she had murdered his mother to steal his father.
- Melissa & Joey: Mel (who is caring for her sister's children) and Joe (the nanny hired to care for said children) eventually fall in love.
- The Nanny: The Unresolved Sexual Tension between Mr. Sheffield and Fran (the titular nanny of Sheffield's children) drove the majority of the series, which ended a single season after they finally got married.
- Nanny and the Professor showed hints of a romance developing between the titular characters ("Nanny" Phoebe looks after "Professor" Harold's children) before the series' cancellation.
- Schneider on One Day at a Time (2017) plays this for laughs since he frequently mentions that his many ex-stepmothers were formerly his nannies as part of his Hilariously Abusive Childhood.
- A variation on Party of Five — oldest brother Charlie, who is promoted to parental figure following the Salinger parents' deaths, begins an on-off flirtation with Kirsten, the nanny hired for his infant brother.
- Who's the Boss?. Angela hires Tony as a housekeeper. She becomes a mother figure for Tony's daughter Samantha and Tony becomes a father figure for Angela's son Jonathan. They begin a long Will They or Won't They? relationship, with marriage being considered.
- The King and I: Anna is hired as a governess for the King of Siam's children. While sparks fly between them, the two of them never act on their love, with the King's death at the end sinking all hopes of a relationship.
- The Sound of Music has the lively nun Maria, who comes to the home of Captain Von Trapp to be governess to his seven children. She was kind to them and brought music back into the household. This caused him to begin to fall in love with Maria and they soon married.
- In Fable III, if you have a child with another player, the child will be assigned a nanny as a stand-in for the other player. Assuming that the nanny is of a compatible orientation, you can then woo them and marry them.