This was a wealthy and influential plebeian clan that numbered in its ranks the conqueror of Sardinia, three times consul, who was the father of the heroic tribunes, Tiberius and Caius Gracchi. These two were victims of their idealism and sense of social justice. Both were killed by reactionary senators within the interval of ten years.

Denarius, L. Sempronius Pitio 148 BCE
The Sempronia were a wealthy and influential Plebeian family, blessed with several consuls during the Republic.
The famed brothers Gracchi were sons of Tiberius senior (twice Consul and Censor) and Cornelia, patrician daughter of Publius Scipio Africanus, who was famous in her own right. She refused to remarry after Tiberius' death and devoted herself to her children, whom she educated and inspired with a sense of civic duty. When a wealthy patrician woman spoke of her jewels, Cornelia pointed to her two sons, saying, "These are my jewels." Cornelia thus became a legend in her own time noted for possessing the virtues of the ideal Roman matron.
Tiberius Sempronius Gracchus and younger brother, Gaius, stepped onto the stage of history between 137-121 BCE at a time when civil unrest presaged the civil war that would ultimately bring the downfall of the Republic. Both served under cousin, C. Scipio Aemilianus (adopted grandson of Scipio Africanus), both ascended to the office of consul, both attacked the status quo and both fell, murdered by their political oponents.