Edda Mellas said Friday Knox got along great with Meredith Kercher at the apartment they shared in Perugia, Italy.
And on The Early Show Friday, Knox's father, Curt Knox, said his ex-wife's testimony is going to bolster his daughter's case. Curt said Mellas heard the shock in Amanda's voice when she found Kercher's body in their apartment on Nov. 2, 2007.
Mellas testified Friday that, in her first call to Mellas, Amanda said she thought somebody was in the house. In her second and third calls, Mellas said, Knox was distraught after Kercher's body was found.
Curt also told Early Show co-anchor Maggie Rodriguez he was "very proud" of his daughter's testimony, saying she answered all the questions she faced articulately and directly. Knox testified in Italian.
Prosecutors say the University of Washington student and her boyfriend killed Kercher during a sex game. Both deny wrongdoing. Another man accused of taking part was convicted and sentenced to 30 years.
Watch CBS Videos Online