As announced last month, former Eldorado actress Polly Perkins has joined the cast of the soap in the role of Rose, who has had little contact with Dot for most of their lives.
EastEnders filming took place at the seaside in Southend, Essex yesterday as the storyline apparently sees Dot track down Rose at her home near the beach.
Scenes shot on the day saw Dot and Rose having "sombre" conversations, hinting at their strained relationship, the Daily Mail reports.
Last month, show bosses confirmed that Dot decides to visit her sister after suffering a bout of hypochondria.
The pair are not on good terms as Rose once embarked on an affair with Dot's first husband Charlie. However, it is thought that Dot is now keen to bury the hatchet.
Perkins's first scenes as Rose will air later in the summer.
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