Sirius considered James his soul mate.

If someone asked a young Sirius how he would live in a world without James he would say it was impossible it happen.

Sirius could play the piano and spoke fluent French.

Sirius truly loved Regulus and was sorry the day he learned of his death.A part of him thought he should have done more for his little brother even if it was irrational.

Walburga didn't immediately burn Sirius from the geanology tree, thinking he would come back begging her for an apology and it was all just another typical Sirius teenage rage.

After all, in her head there was no way her son could really hate her to the point of preferring to live with blood traitors than with her.

It was only when it was clear that he would not return for her what in a fit of rage at Sirius' betrayal of abandoning her that Walburga burned her name from the tapestry.