According to charging documents, San Diego Delgado wrote a letter to a Tyler County judge confessing to the murder of 93-year-old Novell McKissack. On September 4, 1999, 15-year-old Delgado allegedly pried open a window at McKissack's residence in northwest Houston in an attempt to steal items to sell for drug money.
McKissack encountered Delgado in her home, and Delgado allegedly strangled and stabbed her repeatedly.
In the early 2000s, Delgado was convicted of aggravated sexual assault and aggravated kidnapping in a separate case and sentenced to 25 years in a state prison.
Investigators said he wrote the confession letter in 2014 while incarcerated at the Gib Lewis Unit in Woodville.
According to investigators, one of McKissack's neighbors recognized Delgado's photo, which closely matched a composite sketch made of him at the time.
At the time of McKisscak's murder, Ana Rodriguez was just a child. She and her family live in the house where McKisscak lost her life. ABC13 first broke the news to Rodriguez.
Her face lit up with a big smile as she stood in her doorway. Rodriguez used to live across the street from McKissack. She described the elderly woman as sweet and religious.
She reminisced about how McKissack would wave to her as she came home from school.
"She used to teach people how to bake. She embraced the grandma role for everyone. She was sweet," said Rodriguez. "It's a great thing. I'm happy in my heart for that."
Delgado will appear in Harris County court on Wednesday.
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