Impact and Implications: The current study highlights the importance of screening for suicidal ideation for both individuals with traumatic brain injury (TBI) and their caregivers, as findings suggest that thoughts of death and/or suicide are relatively common among both patients and caregivers up to a year post-injury. Moreover, patient suicidal ideation at hospitalization is predictive of reported caregiver suicidal ideation at later time points. Clinicians and rehabilitation specialists may wish to expanding practices of assessing suicide risk in patients to include caregivers, particularly caregivers of patients who endorsed suicidal ideation. Given that these findings demonstrate significant interdependence of suicidality between patients and caregivers, interventions for patients with TBI should include their respective caregivers or even incorporate family systems theories and approaches. Purpose/Objective: Traumatic brain injury (TBI) is associated with depression, anxiety, and even suicidality in individuals with TBI and in caregivers. Moreover, emotional functioning in individuals with TBI is linked with caregiver functioning. However, no known studies to date have examined linkages in suicidal ideation in individuals with TBI and family caregivers. This is especially important in Latin America, where TBI rates are high, and where cultural norms influence family caregiving. This study examined associations among self-reported suicidal ideation in individuals with TBI and their primary caregivers over time in Mexico and Colombia. Research Method/Design: A total of 109 individuals and their primary caregivers completed measures during hospitalization for TBI and at 2- and 4-months posthospitalization. The primary outcome was Item 9 from the Spanish version of the Patient Health Questionnaire-9, assessing for thoughts of death or suicide in the previous 2 weeks. Results: Patients and caregivers reported high levels of suicidal ideation (18.3%-22.4% and 12.4%-15.7%, respectively) at each time point, and suicidal ideation at one time point strongly predicted ideation at the next. When patients endorsed suicidal ideation in the hospital, their caregivers tended to endorse suicidal ideation 2 months later. Although unaccounted for variables could be driving these relationships, they may also provide possible evidence of causal preponderance between patient and caregiver suicidal ideation post-TBI. Conclusions/Implications: Clinicians and rehabilitation specialists can use these findings to inform suicide risk assessment by expanding these practices to caregivers of patients who endorsed suicidal ideation. Interventions after TBI should incorporate caregivers given this study showed significant interdependence of suicidality between patients and caregivers.