What is the test for a cause of action for wrongful death?

Appellant seeks damages for the wrongful death of his mother. "A cause of action for the death of a person caused by the wrongful act or neglect of another" may be asserted by the decedent's surviving children. ( 377.60.) Under this section, "the plaintiff must prove the death was `caused by' the defendant's wrongful act or neglect, i.e., the wrongful act or neglect was a cause in fact of the death." (Bromme v. Pavitt (1992) 5 Cal.App.4th 1487, 1497-1498.) To constitute a "cause in fact," the wrongful act must be a "substantial factor in bringing about" the death. (Id. at p. 1498.)