What is the test for a conviction for child-homicide under section 273ab and second degree murder based on implied malice?

A conviction for child-homicide under Penal Code section 273ab requires evidence showing that a defendant "`"willfully and unlawfully, while having care or custody of a child under eight years old, assault[ed] the child by means of force that to a reasonable person would be likely to produce great bodily injury and . . . which result[ed] in the child's death."' [Citation.]" (People v. Norman (2003) 109 Cal.App.4th 221, 226-227.) A conviction for second degree murder based on implied malice requires that the defendant must have "deliberately performed an act, the natural consequences of which are dangerous to life, knowing that the conduct endangers the life of another, but acting with conscious disregard for that risk of life." (People v. Autry (1995) 37 Cal.App.4th 351, 358.) "`[I]t is not necessary to establish that the defendant intended that his act would result in the death of a human being.' [Citation.]" (People v. Swain (1996) 12 Cal.4th 593, 603.)