In addition, mothers with three or more children were 30% more likely to lose a subsequent child to cot death than those bringing up their first baby.

BBC: 'Lowest ever' infant death rate

He said data showed that in families which had lost one child to cot death, subsequent babies were at an increased risk of dying from the same cause, or from a variety of natural causes, such as meningitis.

BBC: NEWS | Health | The science behind cot deaths

The child's mummified body was found in his cot in March 2010 - eight months after he was last seen alive.

BBC: Kimberley Hainey and son Declan

For example, if you looked at the risk of a cot death among couples in which the mother is under 27, has more than one previous child, with both parents unemployed and are smokers, it increases to approximately one in 200.

BBC: NEWS | Health | The science behind cot deaths