Nero and Agrippina-How and why did Nero plot against Agrippina?

Nero was prophesized by astrologers when he was born that he would become emperor but kill his mother, according to Tacitus (The Annals). Agrippina's reply was "Let him kill me- provided he becomes emperor". This reinforces Agrippina's desire and ambition for Nero to gain this position. After Nero became emperor in AD 54 after Claudius' death, Agrippina exercised power through her influence on Nero by sending official letters to kings and governors and receiving the various …

…and two naval officers to her mansion to execute her. According to Dio Cassius, Agrippina tore open her clothing, exposing her abdomen and cried out, "Strike here, Anicetus, strike here, for this bore Nero". She was clubbed about the head and then dispatched with a sword. Nero is later said to have gazed over her corpse to satisfy himself that she was indeed dead, remarking, "I did not know I had so beautiful a mother".