this should clear it up for you.
That fateful dagger has had an enormous impact on this story, first making an appearance in season one, when Bran is bedridden, freshly crippled after Jaime Lannister pushed him out of a window.
A mysterious assassin attempts to murder Bran with the dagger, but is stopped by dedicated mother Catelyn Stark, who practically cuts her fingers to the bone trying to disarm the assassin. The struggle almost results in Bran’s death, but he is saved by his direwolf, Summer, who tears the assassin's throat out. When the dagger is examined later, it is found to be made of Valyrian steel, with a dragonbone hilt, indicating a royal, possibly Targaryen, heritage.
This is Catelyn’s first clue that the assassination attempt came from someone of great wealth and importance, being too valuable a dagger to belong to the lowly assassin. Thus, Catelyn takes the blade to King’s Landing, where Littlefinger reveals that the dagger once belonged to him, before he lost it in a bet to Tyrion Lannister.
Of course, Littlefinger is telling blatant untruths, as usual, but the lie provokes Catelyn into arresting Tyrion, sparking tension between House Stark and House Lannister, eventually exploding into the War of Five
That fateful dagger has had an enormous impact on this story, first making an appearance in season one, when Bran is bedridden, freshly crippled after Jaime Lannister pushed him out of a window.
A mysterious assassin attempts to murder Bran with the dagger, but is stopped by dedicated mother Catelyn Stark, who practically cuts her fingers to the bone trying to disarm the assassin. The struggle almost results in Bran’s death, but he is saved by his direwolf, Summer, who tears the assassin's throat out. When the dagger is examined later, it is found to be made of Valyrian steel, with a dragonbone hilt, indicating a royal, possibly Targaryen, heritage.
This is Catelyn’s first clue that the assassination attempt came from someone of great wealth and importance, being too valuable a dagger to belong to the lowly assassin. Thus, Catelyn takes the blade to King’s Landing, where Littlefinger reveals that the dagger once belonged to him, before he lost it in a bet to Tyrion Lannister.
Of course, Littlefinger is telling blatant untruths, as usual, but the lie provokes Catelyn into arresting Tyrion, sparking tension between House Stark and House Lannister, eventually exploding into the War of Five