11-20 360, 11-20 360

Veteran served active duty Aug 1967–Aug 1969; his older brother was killed in action in Vietnam in Nov 1968 — a claimed in‑service stressor. Veteran died Oct 2013; appellant is surviving spouse and substituted as claimant.
Original RO decision (Feb 2010) and subsequent appeal focused on PTSD; appellant later asserted dementia intertwined with PTSD. Board remanded for development in 2013 and 2015; hearings held in 2015 and 2017.
Medical evidence: Dr. Carl Carter (Sept 2016) diagnosed PTSD and depressive disorder and opined nexus to in‑service stressor; Dr. Dennis Hill (Sept 2009) supported PTSD evaluation and linked PTSD/dementia in literature. An Aug 2016 VA examiner found the brother’s death a credible stressor but said no prior professional PTSD diagnosis in file to tie dementia to service.
Lay evidence: appellant testified to longstanding symptoms after brother’s death (startle response, nightmares, depression, interpersonal problems, flashbacks, sleep disturbance, obsessive behaviors).
Board found the in‑service death of the brother credible, accepted the medical nexus opinions of Drs. Carter and Hill as well‑reasoned, and gave less weight to the August 2016 VA exam for failing to address Carter’s diagnosis.

Issue	Appellant's Argument	VA/Defendant's Argument	Held
Entitlement to service connection for PTSD	Veteran’s PTSD (manifesting as dementia) was caused by brother’s in‑service death and persisted post‑service	No established prior professional PTSD diagnosis in file; examiner could not relate dementia to service without such diagnosis	Granted: Board found credible stressor, current diagnosis, and medical nexus; service connection for PTSD and depressive disorder established

Holton v. Shinseki, 557 F.3d 1362 (Fed. Cir. 2009) (elements required for direct service connection)
Gonzales v. West, 218 F.3d 1378 (Fed. Cir. 2000) (Board must provide adequate statement of reasons or bases)
Nieves‑Rodriguez v. Peake, 22 Vet. App. 295 (2008) (criteria for probative medical opinion and consideration of medical evidence)
Caluza v. Brown, 7 Vet. App. 498 (1995) (Board must assess credibility and weight of evidence and explain rejections)
Gilbert v. Derwinski, 1 Vet. App. 49 (1990) (benefit of the doubt rule when evidence is in equipoise)