The Dark Shadows Wiki

In the late 1600s, Isaac Collins and his wife Annabella founded the town of Collinsport. His  brother was Amadeus Collins. (The Crimson Pearl)

In 1795, Isaac and Annabella's presumed grandson Joshua and his wife Naomi had two offspring: Barnabas and Sarah.

Joshua had a brother, Jeremiah, and a sister, Abigail.

Barnabas married Angelique Bouchard. Jeremiah Collins married Josette DuPres. Only Joshua survived the events of 1795 and a cousin, Daniel Collins, inherited Collinwood. Daniel had a sister, Millicent, who married Lt. Nathan Forbes.

By 1840, Daniel had married Harriet and killed her after she bore two sons, Quentin the First, and Gabriel. A cousin, Flora & her son, Desmond, lived at Rose Cottage. Desmond married Leticia Faye (possibly the great aunt of Pansy Faye). Quentin was married to Samantha Drew and had a son, Tad. Samantha's sister was Roxanne Drew, who Barnabas turned into a vampire. After Samantha died in 1840, Quentin married Daphne Harridge. Gabriel Collins was married to Edith.

Before 1897 Edith's son Geoffrey Collins had four children: Edward, Judith (born c.1850), Quentin the Second (b.1870) and Carl (also Karl). Edward married Laura the Phoenix and had two children: Jamison and Nora. In 1897, Judith married Gregory Trask, making Charity Trask Judith's step-daughter.

Quentin married a Gypsy, Jenny, and had two children, a boy who died in infancy and a daughter, Lenore. Lenore was the grandmother of twins, Tom and Chris Jennings and their sister, Amy. (Joe Haskell was their cousin!) Jenny's sister was Magda, who was married to Sandor Rakosi. As for Carl Collins, he was murdered by Barnabas!

In the 20th century, Jamison was the father of Elizabeth and Roger. Elizabeth married Paul Stoddard and had a daughter, Carolyn Stoddard. Carolyn married Jeb Hawkes. Roger unknowingly married his own grandmother, Laura the Phoenix and had a son, David. After Laura's "death," Roger married Cassandra Blair (Angelique). Nicholas Blair claimed to be "Cassandra's" brother. Although heavily hinted at, Victoria Winters' parentage was never revealed in the TV series. It was only in the audio play Return to Collinwood that it was learned she was Elizabeth's illegitimate daughter; her father was not identified). Victoria was once engaged to Burke Devlin but eventually married Jeff Clark (the reincarnation of Peter Bradford) before vanishing into the past.