Lisa Willis has said she asked her sister Amanda for help on Facebook because she wanted to get out of the relationship with Mick Philpott.
She deleted the exchanges as she went along so they wouldn't be found, although she told Nottingham Crown Court that Mick Philpott couldn't use a computer.
Ms Willis said her relationship with Amanda had ended when she moved into Mick Philpott's home on Victory Road because he wasn't happy with it and her sister didn't like him.
She said she didn't see Amanda for years before resuming contact on Facebook.
The trial has now stopped for lunch.
More top news
Storm Doris is set to bring severe weather across much of the UK on Thursday as heavy rain and strong winds push in from the west.
President Trump has scrapped protections for transgender students that had allowed them to use bathrooms matching their gender identity.
Prisons will be expected to reform prisoners as well as punish them under new proposals, set to be unveiled on Thursday.