Should posts like this be parent/child?

post #314778 and post #654083

The left side of 654083 is just a higher resolution doujin cover of 314778, but half of 654083 was not in the original. Not sure if I should parent it because of that.

Also, if they do need to be connected, should 314778 be the parent since it was first? I think that's the way it's usually done.

When Danbooru 2 comes along, we may have anonymous pools to deal with situations like these, but in the meantime, they should probably be parented. I'd make post #654083 the parent, even with the text on it, given how much higher its resolution is.