Scorpius hates his father, ever since he found out that he left his mother to die. Scorpius does not forgive Harry, because of him he could never meet Draco.
According to the rumors, Harry Potter left Draco Malfoy to die the day Draco gave birth to Scorpius. He despises his father because after his mother's death, he married a horrible woman whom, remarkably, he does not love. Other rumors say that Harry Potter, the savior of the Wizarding World, performed the unforgivable curse, Avada Kedavra, against the one who said was his love.
After Sixteen years of Draco's death, Scorpius explodes.