DISCLAIMER: I DO NOT OWN HARRY POTTER.

Albus Severus Potter and his father Harry Potter stood in the graveyard in Godric's Hollow, looking upon the graves of Harry's parents, James Potter and Lily Potter, who had been killed while trying to protect him from an evil wizard, Voldemort, when Harry was only a year old.

In 1998, Harry had finally killed Voldemort, avenging his parents and bringing peace to the wizarding world.

The year now was 2021. Harry was 40, and Albus would soon turn 15.

As father and son stood before the graves of Harry's parents, Harry hugged his son saying, "They would have been very proud of you Albus."

Albus responded, "I wish I could have met them, and that you didn't have to suffer a horrible childhood. I shouldn't have used those hurtful words that I used in the last few years towards you. I was stupid, and trying to save Cedric nearly got us all killed. I'm so sorry."

Harry turned to him and said, "Albus! Don't ever demean yourself like that. I should have tried to help you more than I did when you felt alienated after getting into Slytherin. I also used hurtful words towards you and expected too much from you. I'm sorry too."

As father and son hugged each other, Harry said, "You were named after two of Hogwarts greatest Headmasters, Albus Dumbledore and Severus Snape. Severus was also in Slytherin and made some great mistakes, but then he switched sides and became a double agent for the light. He protected me and helped me to destroy Voldemort, for my mother's sake. He was the bravest man I've ever seen."

Meanwhile, in one of the higher worlds, Severus Snape looked down on them. He was satisfied that Voldemort had been destroyed and Harry was now living a peaceful life. He sighed and said, "I wish Lily had lived though. Things would have been so much better had she lived."

Suddenly, he heard a sweet familiar voice say, "Severus. You know that I would never put my life or anything else above my child. And though I am grateful to you for having helped and protected my son, I still feel that you could have made a few better choices. You could have treated him better."

Severus said, "Lily, he is Potter's spawn, and James was the man who bullied me and stole you from me."

Lily retorted, "Were you any better back then, when you hung out with racist bullies like Avery and Mulciber, who eventually joined Voldemort?"

Snape hung his head in shame, remembering the day he had called her 'Mudblood'. He said to himself, "I could have done better."

Suddenly, he heard a mysterious voice say, "If you could, would you change things? Remember, one choice can bring about a thousand changes. Some things may not change at all, some things may change for the better and some others may change for the worse."

Severus thought for a while and said, "Yes, I would."

The voice spoke, "For your love and courage, you will be given a rare blessing: A chance to go back in time, have a rewind in your life and change things in your lifetime".

A blinding white light emerged from nowhere and engulfed Severus Snape as he was sent back in time.

And then, he woke up on his bed in his Hogwarts dormitory in the year 1977, at age 17.