Fire Emblem and marriage go together like a horse and carriage.
One of Fire Emblem's classic features has been confirmed to return in Fire Emblem Fates.
A scan of an upcoming issue of Nintendo Dream and Dengeki magazines translated by Serenes Forest has confirmed the return of S rank supports, and the ability for two opposite-gendered characters to marry and have children should they reach S rank together.
Characters who pair up with the player's created character will have special confession images, though we don't have confirmation of the ability for characters of the same gender to S-rank without bearing a child. In a change from Awakening, the father appears to determine the character's identity while the mother's hair color is passed down.