Cora calls Mr Drewe for his help that night to meet them at the train and take Marigold，so that after she and Edith discuss the Drewes' situation with the rest of the family，Edith could bring her back to Downton in broad daylight. As they train home，Cora smiles at Edith and Marigold，but then spots Mary on the station. Edith quickly gets through the situation when she sees Mr Drewe，asking him to take Marigold to the next station while helping them with their bags. Mary and Robert object to the "adoption" but Cora stands by Edith，and Robert agrees when Cora insists they offer Marigold a home.
Robert notes Edith's obsession with Marigold to Cora after the girl joins Sybbie and George in the nursery. He tells her that there is something about Marigold，a "sense of deja vu"，he cannot quite understand. After the unveiling of the war memorial，Robert tells her he has realized Marigold reminds him of Michael Gregson，and confirms with her the truth，that Marigold is Edith's daughter. Cora asks him not to tell Edith he has guessed，that the secret should remain Edith's a little while longer，to which he agrees. To her delight，he admits he thinks he will love his new granddaughter.
Cora is introduced to Atticus Aldridge and his parents Lord and Lady Sinderby through Rose. She encourages Rose's relationship with Atticus. Lord Sinderby speaks to her about her late father，who like the Aldridge family was Jewish. He asks Cora if it was difficult having a different religion from her father，and if her mother never considered converting to Judaism. Cora does not believe so in both cases，and admits she is not ashamed of her father，citing that her family did not change their name (Lord Sinderbys grandfather had changed the family's name to Aldridge).
When the family joins the Sinderbys for the grouse season at Brancaster Castle，Cora sees Robert is hiding something and repeatedly asks him what is going on. He finally admits he has been having pains in his chest and will be going for tests when they return home. Cora insists he should not be shooting then，and when he has a severe episode，she settles the matter and stops him shooting for the rest of the season，telling Mary she wants to get him home in one piece. When it's determined he has an ulcer，she puts him on a strict diet，which to his dismay does not include alcohol. It ends until Christmas Eve，and she tries to stop him from speaking as he has started drinking again，but later on is amazed when he does speak in praise of their son-in-law Tom and wishing him well，for he did not sound drunk at all. When she asks him how he did that，he told her he was concentrating，citing his training as a soldier.
Cora happily supports Edith's plans to appoint a female Editor for her business after the male one walks out on her. Meanwhile Mary meets a charming race car driver and Cora attends the races，but horror strikes and Henry's rival is painfully killed. She looks visually sad at Finner when the matter is brought up. 1925 proves to be a very stressful for Cora as during at a dinner with the Health Minister her beloved husband began throwing up violently heavy amounts of blood，Cora later ran to his aid and accompaniment him to the hospital. During this time Cora argues with Violet over what is to be done with the Downton Hospital with her pushing to new methods alongside Isboel，Cora is then apptioned the successor of Violet. Cora feels torn as her loyalty first is to her family yet she does want to take the position. Cora eventually takes the position of Chairmen of the Hospital. Later on，when the doors of Downton are opened to the public Cora proves to be fairly unknowledgeable of the great estate. Violet soon storms in and is angry with Cora as she accepted the position. When Violet runs of to France Cora feels responsible for tearing apart the family. When Bertie Pelham proposes to Edith Cora worries over what he will make of Marigold. Cora constantly helps Edith with her difficult situation with Pelham，and pushes for her to tell him the truth. Later when Bertie becomes the new Marquess Cora is very happy and later addresses him incorrectly but it is taken lightly and the two laugh. Cora then comforts Edith when Bertie leaves but is overjoyed when Mary marries Henry.
"I believe there is an answer，which will secure your future and give you a position." - to Mary about marrying Matthew and becoming Countess of Grantham
"No one ever warns you about bringing up daughters. You think it's going to be like "Little Women." Instead they're at each other's throats from dusk till dawn."
"We're alright. Aren't we，Robert?" - talking to Robert after she survived Spanish flue and Lavinia didn't
"Don't worry about me，I'm an American. Have gun，will travel!" - to Robert after his confession of losing most of her money
"Very，very good luck my beautiful daughter!" - blessing Mary right before her wedding
"You are being tested. And you know what they say，my darling. Being tested only makes you stronger." - comforting Edith after her canceled wedding
"Because you are my baby. My beauty and my baby." - saying goodbye to Sybil
"Welcome to the Highlands." - to Robert after being woken up by a bagpipe at Duneagle Castle
"You don't have to give money after every conversation，Mother." - talking to her mother as she pays a visit to Downton for Mary's wedding
"Downton Place. How lovely." - to Robert as they visit the house they may have to move into
"And you never thought to involve me，her own mother?! You，Rosamund! You looked at that little girl，and you never thought it was my business too?!" - to Violet and Rosamund for never telling her about Edith and Marigold.
"We have quite the contrary daughter." - Season 6 Episode 8 - talking about Mary and spouse options for her to Lord Grantham.