Final answer:
Nina's family's custom for newly married couples to live with her family is an example of a matrilocal residence, where the couple lives with or near the bride's mother or her maternal relatives, and is associated with matrilineal descent.
Step-by-step explanation:
It is a custom in Nina's family for newly married female members to continue living with their families, along with their husbands. Thus, Declan who recently got married to Nina also moves in to live with her and her family. In the context of the different residence patterns, this is an example of a matrilocal residence.
Matrilocal residence is associated with societies practicing matrilineal descent. In this postmarital residence pattern, the newly married couple establishes their new household with or near the bride's mother or the bride's mother's relatives. In this case, at marriage, the bride remains within her household and/or family group, while the groom leaves his parents. Their future children will belong to the bride's lineage.