Sirius's appearance may seem though and mean. But he is quite gentle and kind. But he sometimes can be stong-willed and occasionally stubborn. But he loves harry and will not let anything come in the way of that relationship.
You mean "Blacks"? Several: Andromeda, Narcissa, Bellatrix, Sirius, Regulus, Walburga (painting)...
I do not believe they gave us this piece of information in the books.
It was ''nice one james.''
His biggest flaw is his inability to let go of the past.
Sirius Black's boggart was never revealed, but some fan theories say it would be the bodies of James or Harry, as losing them were his biggest fears.
D.i.d
At school Sirius was one of the four Marauders, his best friend were James Potter, Remus Lupin and Peter Pettigrew. After Peter betrayed Sirius was no longer his friend. James was dead and Remus thought that Sirius was the reason why. However once his name was cleared Remus and Sirius became friends again.
If you are referring to the portrait on the second floor in Grimmiauld Place, it is Sirius Blacks mother.
Well , no they are not ..Sirius Black is known to be Harrys GODfather with wishes from his dad but there is no blood relation and the weasleys are not related by any way ..:)
Sirius is Harry's godfather. Sirius Black is Harry's godfather.Harry is sirius's Godson.
It is not real. Sirius is a two-star system containing only Sirius A and Sirius B.
Sirius is a binary star system Sirius A and Sirius B.The distance separating Sirius A from B varies between 8.1 and 31.5 AU. (See related question).