Group marriage in SF

Alternative Family Arrangements

Group marriages, poly/nonmonogamous, sexuality separated from childrearing, etc.

• Block, Francesca Lia. Dangerous Angels: The Weetzie Bat Books (1998). This collects five short novels in one book. Weetzie Bat (1989) - Witch Baby (1991) - Cherokee Bat and the Goat Guys (1992) - Missing Angel Juan (1993) - Baby Be-Bop (1995)
• Dorsey, Candas Jane. Black Wine
• Grae, Camarin. Stranded (In the protagonist's home world, 3-way relationships exist and are respected, although it is acknowledged that they can be difficult. On Earth, 3 of the characters in this novel decide to attempt such a thing also.)
• Heinlein, Robert. Friday and others
• Le Guin, Ursula. The Ekumen / Planet O stories: "Mountain Ways" and "Unchosen Love" [four person marriages are the social norm]

Male Primary Child Care-Takers

• Brantenberg, Gerd. Egalia's Daughters
• Bujold, Lois McMaster. Ethan of Athos
• Dodderidge, Esme. The New Gulliver
• Jones, Gwyneth. Life ("Spence")
• Wen Spencer
• Tepper, Sheri. The Gate to Women's Country. At 5, boys are sent to live with the men in the military camps.
• Varley, John. The Gaean Trilogy, v. 3: Demon [not a social norm, but an interesting daddy role]
• Wells, John J. [pseud. for Marion Zimmer Bradley & Juanita Coulson], "Another Rib," The Magazine of Fantasy and Science Fiction (June, 1963) [when an all-male crew returns from outer space to discover Earth destroyed, they have to figure out how to reproduce with each other]