The web search results contain multiple instances reporting the core details of the event (shooting in Southeast D.C. involving a nephew and a mother), but these reports appear to stem from the same set of initial reporting/sources, making it difficult to confirm corroboration from 2+ *independent* news organizations based solely on the provided snippets. The evidence is heavily concentrated on the narrative from the initial reporting.

The web search results mention an arrest and charge related to the incident, specifically naming Maurice Jackson and the charge of second-degree murder. However, the evidence provided does not contain two or more independent news sources reporting this specific arrest and charge. One web search result mentions the arrest, but the other mentions a different arrest (Gracie Yates) or a different murder charge (Florida man).

The claim that Olivia Graves was in school to become an EMT is mentioned in the narrative context of the web search results, but no other independent sources or authoritative references corroborate this specific detail. The evidence is limited to the initial reporting.