It's the night before the wedding but Cathy can't enjoy her drink-up as she's obsessed by a scuff on the wall Marcus made, and the sisters run in to Cat's old school bully.

Cat decides to take Cathy on their own sister honeymoon to cheer her up. Marilyn finds Colin's missing will and, together with Tess, they need to tell the girls the shocking news.

Catherine 'Cathy' Walcott and Catherine 'Cat' Walcott only discovered one another existed after their dad dropped dead. Having finally come to terms with the fact they are sisters, they are now reeling from the news that they also have a brother, Callum - and that Cathy just snogged him. As Cathy struggles with the ethics of fancying a sibling, Cat is determined to welcome Callum to the family, while Callum isn't sure what family means any more.Cat's mum, Marilyn, is furious to learn she wasn't Colin's only mistress and sets about tracking down his other secret lover, Angela, starting a chain of events that nobody expected. Meanwhile, Cathy's mum, Tess, decides to have some fun with her late husband's legacy and embarks on an ill-advised luxury spending spree.