The Wiltshire coroner says the cause of 3 year old Bryn Anderson's death is unclear but has recorded a verdict of unlawful killing.
The bodies of 11 year old Jack and 3 year old Bryn were found next to the body of their father, Graham Anderson, in a flat in Tidworth in September last year.
The coroner earlier recorded a verdict of suicide into the death of Graham Anderson. He said 11 year old Jack was also unlawfully killed by his father.
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Stephen Gilbert who was the constituency's MP from 2010-15 will contest the St Austell & Newquay seat for the Liberal Democrats on 8 June.
It'll be dry and sunny to begin with this Bank Holiday weekend in the West, but with showers just around the corner.
It's a mixed weekend for the South West ahead with sunshine on Saturday but rain and showers across Sunday and Monday.