The Laucopids are the four children given birth by The Lady and the spouses they took who later sealed their father, Vear into the Void, eventually separating from the continent of Brant and creating Asgard.
The quadruplets born by the Lady were (in order of birth) Liliani, Lif, Hallr, and Holmdis. The two females (Lif and Holmdis) are identical twins; the two males (Liliani and Hallr) bear a striking resemblance to each other but are not identical.
Since they were joined in marriage to their spouses when they took part in the forming of the Seal, the spouses acquired the immortal and mystical qualities of the quadruplets as well. Liliani and Hallr had taken Tijana and Helen as wives (respectively); Lif and Holmdis had taken Montepulciano and Matti as husbands.