Who is The Lindgren Family from Drowning Ruth and what is their importance?

Amanda Starkey's childhood friend in Nagauwkee, Mary Louise Lingren works in Heinzelman's Bait and Tackle. Mary Louise, who is one of nine children, and husband George are expecting again, having lost five babies to miscarriage in five years of marriage. On the night that Mathilda (Starkey) Neumann drown in Nagawaukee Lake, Amanda brought Mary Louise a newborn, Imogene, said to belong to a hired girl who died in childbirth. Imogene (Genie) is, in fact, Amanda's newborn. Mary Louise is so joyful that she does not notice that Amanda and Ruth wear nightgowns and appear frozen and that Amanda is covered with blood.