Lisa Montgomery's sister speaks out ahead of scheduled federal execution

In 2004, Lisa Montgomery was arrested after she murdered 23-year-old Bobbie Jo Stinnett in Missouri, who was eight months pregnant. She was later convicted of capital murder and federal kidnapping -- leading to a death sentence. Now on the eve of her execution, her sister, Diane Mattingly, spoke to CBSN's Lana Zak about why Montgomery should be given clemency for her crimes. CBSN is CBS News’ 24/7 digital streaming news service featuring live, anchored coverage available for free across all platforms. Launched in November 2014, the service is a premier destination for breaking news and original storytelling from the deep bench of CBS News correspondents and reporters. CBSN features the top stories of the day as well as deep dives into key issues facing the nation and the world. CBSN has also expanded to launch local news streaming services in major markets across the country. CBSN is currently available on CBSNews.com and the CBS News app across more than 20 platforms, as well as the CBS All Access subscription service. Subscribe to the CBS News YouTube channel: http://youtube.com/cbsnews Watch CBSN live: http://cbsn.ws/1PlLpZ7c Download the CBS News app: http://cbsn.ws/1Xb1WC8 Follow CBS News on Instagram: https://bit.ly/2FG5yti Like CBS News on Facebook: https://bit.ly/2FBZWUG Follow CBS News on Twitter: http://twitter.com/cbsnews Subscribe to our newsletters: http://cbsn.ws/1RqHw7T Get new episodes of shows you love across devices the next day, stream CBSN and local news live, and watch full seasons of CBS fan favorites like Star Trek Discovery anytime, anywhere with CBS All Access. Try it free: http://bit.ly/1OQA29B