So I'm reading The Deathly Hallows in French and I have come to the scene at Shell Cottage where our hero trio are about to apparate to Diagon Alley to attempt to break into Gringott's.
Hermione expresses her horror at having to carry the captured wand of Bellatrix Lestrange. Harry tells her it should help her live the part. Ron tells her to imagine all the powerful magic that has been done with that wand.
Ron's comment only serves to make matters worse as Hermione points out, with absolute disgust, that Bellatrix had used that exact wand to torture Neville's parents into madness and then to kill Sirius Black.
Harry's immediate reaction is one of revulsion. He expresses the wish to throw the wand away, to get as far from it as he possibly can.
It's too bad he didn't remind himself of Priori Incantatem, the spell that forces a wand to reveal the spells it has previously cast in reverse order.
We saw Priori Incantatem in the graveyard in The Goblet of Fire when Voldemort returns to bodily form -- Harry's wand forces the Dark Lord's wand to spit out shadows (albeit talking shadows) of its most recent victims, including (I believe erroneously) Cedric Diggory and Harry's parents -- and, earlier in the seventh novel, Harry reminds Hermione and Ron that, by using Priori Incantatem on Hermione's lost wand, the Death Eaters will soon learn that Harry's original wand had been broken.
In that graveyard scene, remember, the shadows that emerged from Voldemort's wand of his recent victims were actually able to speak to Harry and to take steps to protect him as he made his escape. In a way, while simply shadows of spells past, they were also thinking beings.
So it's too bad that Harry doesn't think to perform Priori Incantatem on Bellatrix's wand so as to get a chance to speak, at least briefly, to his godfather. I'm not sure what good it would have done any one, to be honest -- it's not like Sirius would have any great insights into the Deathly Hallows or how to break into Gringott's or what the last three Horcruxes were -- but it might have given Harry, Hermione and Ron a welcome moment with their beloved mentor.