I don't get why the fandom likes to say Lily and Ginny look really similar to each other.
I mean, yeah, they both have red hair (different shades of red, btw), but all their other descriptions are very different, and the two probably don't look alike at all.
Let's start with their hair:
She was a very pretty woman. She had dark red hair and her eyes — her eyes are just like mine, Harry thought, edging a little closer to the glass. Bright green — exactly the same shape
(PS)
It was one of the girls from the lake edge. She had thick, dark red hair that fell to her shoulders and startlingly green almond-shaped eyes — Harry’s eyes.
(OotP)
Ginny, on the other hand, is described with "flaming red" hair, so it's likely something like this:
Plump little Mrs. Weasley; tall, balding Mr. Weasley; six sons; and one daughter, all (though the black-and-white picture didn’t show it) with flaming-red hair
(PoA)
where two enormous gray feet stood on the smooth Chamber floor. And between the feet, facedown, lay a small, black-robed figure with flaming-red hair.
(CoS)
As Lily's hair is described as "dark red", so we're probably talking on this sort of more auburn color while Ginny's (and her brothers) hair would be more orange (Lily - Left, Ginny - Right):
Also, Lily is described as having "thick" hair, while Ginny isn't. So, I usually imagine Ginny's hair as straight while Lily's has more waviness and volume to it.
Their eye color (and shape) is also different:
As I mentioned above, Lily has bright green almond-shaped eyes like Harry, while Ginny's eyes are described as:
He forced himself to look directly into her eyes, noticing as he did so that they were precisely the same shade of brown as Ginny’s.
(DH)
They are built really differently as well, and their facial structure is likely quite different too. Ginny is often mentioned to take after Molly (short with brown eyes) and we know Molly is plump and rounder:
Mrs. Weasley was marching across the yard, scattering chickens, and for a short, plump, kind-faced woman
(CoS)
So, Ginny likely has a similar build, short and stocky (if likely less plump as she's more sporty. Also she didn't have 7 pregnancies yet which can also affect a woman's build), and has a round face. She is mentioned to be noticeably short of repeatedly:
“You need more persuasion?” she said, her chest rising and falling rapidly. “Very well — take the smallest one,” she ordered the Death Eaters beside her. “Let him watch while we torture the little girl. I’ll do it.” Harry felt the others close in around Ginny. He stepped sideways so that he was right in front of her, the prophecy held up to his chest.
(OotP)
Harry looked over the top of Ginny’s head to see Dean Thomas holding a shattered glass in his hand
(HBP) - Harry who's about 5'11 in HBP can easily see over the top of Ginny's head.
Lily, on the other hand, is Petunia's sister and likely shares some familial resemblance. Petunia is tall (for a woman, not tall-tall), thin, and she has a thin face:
Aunt Petunia’s thin, horsey face now appeared beside Uncle Vernon’s wide, purple one. She looked livid.
(OotP)
Plus, Lily is implied to be taller than Pettigrew (who I estimate at about 5'2 and taller than Ginny):
His mother and father were beaming up at him, sitting on either side of a small, watery-eyed man Harry recognized at once as Wormtail
(OotP)
Also when she stands next to a 5'11 James, she isn't mentioned to be shorter than him by a full head (like Ginny is and which is the kind of thing Harry often mentions):
The tall, thin, black-haired man standing next to her put his arm around her
(PS)
I always imagined Petunia as tall and thin and Lily not shorter by much. So, Lily is somewhere around 5'6-ish, I think, which is a bit taller than average, while I imagined Petunia is a little taller. And Lily would likely have a thin, slightly longer-looking face, especially compared to Ginny. (Harry too, is mentioned to have a thin face, like his mom).
Ginny, like the rest of the Weasleys, is very freckled:
My father told me all the Weasleys have red hair, freckles, and more children than they can afford.
(PS)
Mr. Weasley, Fred, George, and Ron in a cloud of rubble and loose chippings. Aunt Petunia shrieked and fell backward over the coffee table; Uncle Vernon caught her before she hit the floor, and gaped, speechless, at the Weasleys, all of whom had bright red hair, including Fred and George, who were identical to the last freckle.
(GoF)
Charlie was built like the twins, shorter and stockier than Percy and Ron, who were both long and lanky. He had a broad, good-natured face, which was weather-beaten and so freckly that he looked almost tanned;
(GoF)
Note Fred, George, and Charlie, like Ginny are more similar to Molly, and all are covered in freckles.
Whereas Lily (or Petunia) is never mentioned to have freckles, and most likely doesn't have any. Her face is only ever described as white. If she did have freckles, Harry would have mentioned it since it's the kind of thing he notices. Especially considering how excited he is whenever he sees his parents' faces.
So, Ginny and Lily don't look at all alike, not even their hair is the same kind of red and I find all the jokes about Oedipus complex or Hinny looking just like Jily make very little sense when you look at their actual descriptions in the books. These two women look nothing alike (besides red hair (in different shades!) and white skin), so it just kind of annoys me when they're treated like look-alikes in fanon.
