Authorities say her then 19-year-old boyfriend killed her 63-year-old mother, Geraldine Lloyd, in January 2006. Lloyd's body was found about six months later, buried in her backyard.
The boyfriend, Christian Olsen, was convicted of killing a neighbor in June 2007 and was sentenced to death.
The Bryan-College Station Eagle reported that Sifuentez said little during her sentencing hearing except to admit her guilt.
QUICK HEADLINES | MORE TEXAS | GET NEWS ALERTS
-----------------------------------------------------------------------------------------------
ABC13 SOCIAL NETWORKING
Find us on Facebook® | Follow us on Twitter | More social networking
-----------------------------------------------------------------------------------------------
MORE FROM ABC13
ABC13 widget | Most popular stories |
Street-level weather
ABC13 wireless |
Slideshow archive |
Help solve crimes
-----------------------------------------------------------------------------------------------