Last week, we told you how meth doesn't really foster good maternal instincts.
Here's another case in point.
Monica McCarrick, a 29-year-old mom on meth, will be in prison for life after a jury decided she was completely sane when she killed her twin daughters with a samurai sword back in October 2010.
KTVU reports that McCarrick, a Fairfield resident, tried to say she was innocent because she was insane when she slashed her 3-year-old twins, Tori and Lily Ball. McCarrick allegedly tried to commit suicide after the slayings by cutting herself and setting her third-floor apartment on fire.
When police arrived, they found the twins with multiple stab wounds in the doorway of the burning apartment.