Suffolk Police has confirmed that the Independents Police Complaints Commission is to investigate claims that police officers visited Fiona Anderson the day before her death.
A spokesman said the officers spoke to her via intercom after reports that a man had been stabbed near her home by an unknown offender.
Post mortem tests on Ms Anderson's three children have proved inconclusive and further tests will be conducted.
More top news
Emily Middlemas has been kicked out in the X Factor semi-finals - leaving 5 After Midnight, Saara Aalto and Matt Terry through to the finals
Prince Harry has visited a children's home founded by the controversial religious sect known as the Moonies during his tour of the Caribbean
Cloud continues rolling in from the west overnight which, combined with fresher winds will keep temperatures above freezing here.