An extensive body of evidence shows the impact of being the direct victim of a serious assault. However, much less is known about the impact on the family and close relatives of victims, who may be considered indirect victims. Based on analyses of the 2014 Adult Psychiatric Morbidity Survey, a face-to-face, cross-sectional probability-sample survey of 7519 adults aged 16 and over in England, this article estimates what proportion of the population was closely related to a victim of serious assault, and whether this experience was associated with a higher prevalence of feeling unsafe, depression and anxiety disorder, post-traumatic stress, self-harm, and suicidality. Descriptive and multivariable regression analyses were conducted, adjusting for complex survey design and potentially confounding factors. Results show that one in twenty adults (4.5%, n = 345) was closely related to a victim of serious assault (95% confidence interval (CI):4.0-5.2%). Close adult relatives of assault victims were more likely than the rest of the population to have been direct victims of violence and abuse themselves, to have experienced multiple other adversities, and to live in more deprived neighbourhoods. However, even when controlling for these experiences, relatives of victims had adjusted odds of feeling unsafe in the neighbourhood where they lived 2.36 times higher than the rest of the population (CI:1.26-4.44), and their odds of having a depressive or anxiety disorder were 1.37 times higher (0.99-1.90). These analyses indicate that relatives in England may already be vulnerable, with potential to also be further affected by the experiences of family members. To more fully account for the effects of violence in society, research with indirect victims of serious violence in the context of their own experiences of direct victimization and wider adversities is required. This could be factored into a broader remit for victim support services which includes support for victims' families.