Timeline

The Before	Marcella Longbottom married her brother’s best friend. This would not at all have been notable, except she had to marry down in order to do so. It was very clear to all who saw that they were absolutely besotted with one another, though, something that has not waned in the years since.
March, 1881	Their union is blessed with their first child. Louisa Ginevra Weasley is named after her aunt, with whom Marcella is quite close. From birth, her shock of red hair marks her as her father’s daughter, and her easy nature marks her as her mother’s.
1881 - 1884	Hers is the typical early childhood of learning to support her own head, developing speech (her first word, Papa), and other such things. Most of her early memories take place at a quidditch pitch, and indeed her first ‘memory’—whether she actually remembers it or has just been told about it many times remains to be seen—is of her mother labouring with her sister at the Quidditch World Cup! This period sees Caroline born following that incident in 1883, and Wesley born in the autumn of 1884. 1884 also sees the passing of Aunt Gladys and her husband in the Laughing Plague.
1885	Aunt Louisa dies after giving birth to Auberon, which stresses this Lou out immensely. This leads to a great deal of accidental magic, including accidentally setting a swing on fire.
1886-1891	In January, her father is attacked at the shop he owns, sending him into a coma. Louisa doesn't understand what the word means, but to her, it means he is there but isn't, and Mama is dreadfully sad. Though he awakes in April, he is not the Papa that Lou remembers, and it takes the better part of a year before either he returns to his old self, or Lou just adjusts to Daddy 2.0. In 1886, Louisa begins her lessons with a governess, where she does well, but often becomes anxious about her performance. She is very focused upon being perfect—to her father, whom she idolizes, and as a role model for her young siblings—and so has a difficult time asking for help. She develops a habit of biting her fingernails, no matter what her governess does to try to get her not to. Celeste is born in 1886 and Linton in 1888.
1892	Mama is expecting again (delivering in June), and Hogwarts is on the horizon! Louisa is excited to walk the same corridors as her older cousins, but anxious about living up to expectations—especially her own.