Some of things made using Weirwood - The Moon Door, Arryn throne, the doors in the House of Undying, the doors/chairs in the House of Black and White, the High Septon’s staff, the table in the KG tower, Ned’s bed in Winterfell, Val’s brooch, Morna the warrior witch’s mask,  etc. The Wildlings use it for weapons (The Thenns have Weirwood spears) and Bloodraven’s army ‘Raven’s Teeth’ used weirwood bows.

Jaime and Theon both have dreams in proximity to weirwood. Jaime’s is on a weirwood stump meaning it’s still connected to the Weirnet. Theon’s is on Ned’s weirwood bed.

Both Jaime and Theon exhibit guilt in these dreams. Roose Bolton mentions the Trident and Ruby Ford to Jaime before he leaves Harrenhal and Jaime recalls the tourney at Harrenhal because he used the route to get there. In his dream he sees Rhaegar. Over at Winterfell, Theon sees Lyanna in his dreams. 

And that’s why it’s not clear if Theon’s dream is prophetic in nature, or manipulated by someone or just him having a simple dream.

But there were others with faces he had never known in life, faces he had seen only in stone. The slim, sad girl who wore a crown of pale blue roses and a white gown spattered with gore could only be Lyanna. Her brother Brandon stood beside her, and their father Lord Rickard just behind. Along the walls figures half-seen moved through the shadows, pale shades with long grim faces. The sight of them sent fear shivering through Theon sharp as a knife. And then the tall doors opened with a crash, and a freezing gale blew down the hall, and Robb came walking out of the night. Grey Wind stalked beside, eyes burning, and man and wolf alike bled from half a hundred savage wounds. - Theon, ACoK

Why is Lyanna wearing a crown of winter roses in Theon’s dream, with a white gown splattered in gore? Unless the statue in the crypt used to wear a crown of flowers? But Ned mentions a garland of roses and only thinks of them as a crown of roses in his dreams. And then Theon’s dream ends with Robb/Grey Wind walking in with wounds and this makes it look almost prophetic. Could this be because of the weirwood bed?

Bavarian beauty.

Bayerische Schönheit.