Based on the title prompt "White Roses" from Alisha Vane. Not sure if this depressing bit is what you meant.
Probably very short and not very good, but I wanted to get something posted before I left my computer for a while.
A single white rose over a single grave marked the day Fred Weasley was buried.
George Weasley was the one to lay the rose down. There was no other choice. George was Fred's twin, his other half.
Someone cast a single spell, and for the next sixty years the white rose remained on the grave, until the twins were together once more.
Albus Potter remembered a story, a story told by his Uncle George when he asked why George avoided mirrors. Uncle George told him about the rose, and then showed him the rose, still on the grave.
So for the first funeral Albus Potter ever went to, he brought a white rose, already enchanted, to lay on Scorpius's mother, Astoria Greengrass' grave.
It went on from there. Teddy Lupin found out what Albus did for a woman he hadn't ever met. Teddy Lupin, with his blue shock of hair, went and purchased two white roses for two side-by-side graves.
Teddy was shocked to see that when he arrived at the graves, there were already two white roses. He looked around, half expecting to see Harry somewhere, smiling.
Remus Lupin and Nymphadora Tonks had two white roses.
Victorie Weasley stood straight-backed, one arm around Dominique and one around Louis. Apolline Delacour was the next to go, taken by dragon pox far too soon. All three siblings carried a white rose.
There were no deaths, not for a long time, until one day Molly Weasley passed.
There were so many white roses that the grave couldn't even be seen.
The tradition of the white roses carried on for a long time. White roses lain on a grave, symbolizing innocence lost or purity broken. Whites roses lain on a grave, for the dead.