06/01/2011 AT 12:05 PM EDT
Lee Anthony took the stand Wednesday in his sister Casey's murder trial
, and described a "combative" confrontation with her as well as details of his desperate search for Caylee and
Casey during the month the 2-year-old was missing.
According to Lee, Casey Anthony kept insisting to her mother, Cindy, who testified Tuesday she didn't see her granddaughter for weeks, that Caylee was with her nanny, but was asleep and needn't be disturbed. Casey meanwhile was adept at avoiding him. "I went on myspace and Facebook to find where Casey might be. I texted her," Lee said. "[She wrote back] 'I'm busy. I'm out with my friends. I'm doing my own thing.' She hung up on me."
The next Lee saw Casey was at the family home on July 15, 2008, he testified. As he entered the house, he passed Casey's white Pontiac in the garage. He described the smell as "very potent, very strong."
Inside the house, Lee says he confronted a "combative" Casey. "I said I could go get Caylee," he testified to an attentive jury. "There was no excuse why anyone couldn't go get her. [But] she said she didn't want to disturb Caylee."
Casey watched Lee intently, trying to catch his eye as he stepped off the stand for a break. When he glanced at her, she smiled weakly. He did not smile back as he left the courtroom.
Casey, 25, is charged with seven counts in her daughter's death, including first-degree murder. She could face the death penalty if convicted.