Why did a Texas brother fatally stab his twin sister?

Benjamin Elliott, 17, was charged with fatally stabbing his twin sister, Meghan. At trial, his defense attorneys insisted he was sleepwalking when he killed her. Would a jury believe it? Erin Moriarty reports in the season premiere of "48 Hours." #48hours #crime #mystery Each weekday morning, "CBS Mornings" co-hosts Gayle King, Tony Dokoupil and Nate Burleson bring you the latest breaking news, smart conversation and in-depth feature reporting. "CBS Mornings" airs weekdays at 7 a.m. on CBS and stream it at 8 a.m. ET on the CBS News app. Subscribe to "CBS Mornings" on YouTube:    / cbsmornings   Watch CBS News 24/7: https://cbsnews.com/live/ Download the CBS News app: https://cbsnews.com/mobile/ Follow "CBS Mornings" on Instagram:   / cbsmornings   Like "CBS Mornings" on Facebook:   / cbsmornings   Follow "CBS Mornings" on X:   / cbsmornings   Subscribe to our newsletter: https://cbsnews.com/newsletters/ Try Paramount+ free: https://paramountplus.com/?ftag=PPM-0... For video licensing inquiries, contact: [email protected]