The Source's Heir

The Source's Heir was the half-demon son of Cole Turner and Phoebe Halliwell. His conception and birth had been planned and manipulated by the Seer, an evil prophetic woman who could see into the future. However, she unfortunately did not foretell her own demise. 
The union between the then-Source of All Evil Cole and the Charmed One Phoebe created a tremendous concentration of power. Even as a two-month-old fetus, he was able to perform terrible yet nonetheless spectacular feats of magic through his mother. Against this power, even demons thought impossible to be vanquished, perished.