Laima belongs to a deep Indo-European pattern in which destiny is imagined as thread and its keepers as women who spin, measure and cut. In Latvian song Laima is sometimes one and sometimes three, and she is joined by Dekla and Karta, the trio setting, apportioning and ending the thread of a life, a Baltic counterpart to the Greek Moirai, the Roman Parcae and the Norse Norns. What is distinctive is how little of this is antiquarian: laime, from the same root, is still the ordinary Latvian and Lithuanian word for "happiness" or "luck," and Laima's association with childbirth, marriage and women's fortune kept her closer to daily life than the sky-gods. Her decree is fixed at the moment of birth, which places her at the exact seam where the cosmic order of Dievas meets the contingency of a single human life.
Latvian sources do not always divide the three sisters' labour the same way, but one common scheme gives Dekla charge of children, Karta charge of adult life, and Laima the final word together with luck and childbirth, though the dainas often collapse all of destiny into Laima's name alone. The modern Latvian neopagan movement Dievturi, founded in the 1920s, calls the three collectively "the three Laimas," reading the triad as aspects of one fate-power, a twentieth-century theological tidying of material the old songs leave more fluid.