Was Voldemort Aware of Their Blood Connection?

Question

Note that this is a two part question. In Harry Potter and the Deathly Hallows, Chapter 35, this is stated:

‘He took my blood,’ said Harry.

‘Precisely!’ said Dumbledore. ‘He took your blood and rebuilt his living body with it! Your blood in his veins, Harry, Lily’s protection inside both of you! He tethered you to life while he lives!’

Was Voldemort ever aware of this tethered connection, and if so, when did he become aware of it? Also, what would happen to Harry (and Voldemort) if Voldemort were to try to kill him for a second time? Obviously the fragment of Voldemort's soul would be destroyed, however, what would happen if he attempted to kill him again? Would this tethered connection still exist?

Answer 1

Voldemort certainly seems aware that by using Harry's blood to recreate his body, he would bypass the protection that kept him from killing Harry the first time and left him unable to touch him. That was why they went through the hassle of getting him away from Hogwarts, rather than using any old wizard's blood.

From the graveyard scene in Goblet:

But the blood of a foe…Wormtail would have had me use any wizard, would you not, Wormtail? Any wizard who had hated me…as so many of them still do. But I knew the one I must use, if I was to rise again, more powerful than I had been when I had fallen. I wanted Harry Potters blood. I wanted the blood of the one who had stripped me of power thirteen years ago…for the lingering protection his mother once gave him would then reside in my veins too.…

So my answer is YES, Voldemort knew he was creating some sort of blood connection between him and Harry, while obviously not knowing he had just made Harry effectively immortal.

As to the second part of your question, all indications are that Harry lived because of Voldemort's blood, not because of the fragment of Voldemort's soul. So even if Voldemort had tried to kill Harry a thousand times after his first attempt, he would fail every time so long as his blood still had Harry's blood.

Answer 2

No, Voldemort sought only to tear down the protection that Harry had gained from Lily.

Voldemort was extremely desperate to refute the claims that he was beaten by a mere child. He would do anything to stop Harry from existing and thus would never willingly tether harry to life.

I can touch him now.

Goblet of Fire - Voldemort Talking to Death Eaters about Harry Potter

It is evident throughout the series that when Voldemort goes after power or seeks to accomplish something he often overlooks things he is extremely arrogant in that regard. In this instance he wanted to undo the protection which initially caused his downfall. He found a solution and did not bother to look further into it, his arrogance leading him to believe that what he thought was correct. He is rarely seen (if ever seen) to second guess his choices, where a wiser wizard may take a step back and research he starts to plan how to accomplish his newly found solution through any means necessary.

if Voldemort were to try to kill him for a second time?

Well this is largely circumstantial, after Harry is killed the first time he sacrifices himself causing the same protection that Lily granted him. Voldemort does try to kill Harry during the second phase of the Battle of Hogwarts but his curses do not stick. Example: The body bind curse placed on Neville.

Would this tethered connection still exist?

The sacrificial magic used makes it impossible to know, as we'd have to draw a lot of assumptions about things that have no other evidence in canon. The fact is that from the moment Voldemort kills Harry in the forest his fate is sealed.

If he'd struck Harry in the Graveyard during GoF the same events would follow as from the forest scene in DH. However, there would be no sacrificial magic involved so we have no idea what would happen.

A Theory

From the sounds of the other Answer here and the referenced Answer in the other question, along with your quote. It sounds like Voldemort turned himself into a makeshift Horcrux for Harry. Whilst Voldemort still existed Harry was tethered to the living world. In which case Voldemort would never be able to "kill" Harry whilst he was himself alive.

Obviously it is not a complete Horcrux it seems more complex and less dark of a creation, using merely the blood rather than the indescribable dark magic required for a Horcrux. If it were a complete Horcrux we'd have the whole Voldemort kills the Horcrux in Harry but in reverse when Harry killed Voldemort.

TL:DR read the first line.

Answer 3

No.

It's a safe assumption that he wasn't aware, since that blood connection was what prevented him from killing Harry in the Forest towards the end of HP and the Deathly Hallows. Quoting from this answer:

Because Voldemort took Harry's blood for the resurrection potion in Goblet of Fire, and took in Lily's enchantments, Lily's enchantments in Voldemort's blood kept Harry tethered to life as long as Voldemort was himself alive.

If Voldemort had been aware of the blood connection before trying to kill Harry, he would have known he wouldn't be able to, which he obviously didn't know. It's also unlikely that he realised in the last hour of his life why Harry hadn't actually died, since too much was going on for him to stop and think about it.