Lacson was last seen on the morning of August 27, 2007, when her daughter dropped her off at her boyfriend's home in the Makakilo area of Honolulu, Hawaii. She has never been heard from again. She was homeless at the time of her disappearance and had no contact phone number, but she kept in regular touch with her eleven children and attended family gatherings. Her children reported her missing after they didn't hear from her for about six weeks.

Lacson frequented the Wai'anae beach area at the time she went missing, and also stayed at friends' houses. Little evidence is available in her case; the circumstances of her disappearance are unclear.