Percy Jackson grandson of voldemort

The giant war is over. Jason and a few others from both camps died but most survived. The remaining demigods of the 7, Nico, will, thalia and Reyna are made gods.
They were hoping to settle down and live normally for a while. But when Percy and annabeth go to sally Jacksons some strange people show up claiming Percy has another evil grandpa, and that life must be put on hold.

The battle of Hogwarts is over and Voldemort is dead. Harrys year is going back to Hogwarts to redo their 7th year and are hoping that it might actually be normal for once. So when Dumbledore shows up and tells them Voldemort had a grandson and he was coming to Hogwarts harry is not impressed. He would definitely be evil. This would be another difficult year.