Dattebayo Luna and Ginny, this chapter should answer your question:
The four sisters appeared in a brilliant show of blue lights, which would have been wonderful to the eyes had anyone been around to see it. All of the other students were already inside and seated. The four sisters, dressed in their respective uniforms, walked into Hogwarts just in time.
"Okay," a woman said, "In a few minutes, Professor Dumbledore, headmaster of Hogwarts, will be calling for the first years to enter. Those of you who are not first year students, but are new, will be expected to enter as well."
The four sisters were listening; Paige and Phoebe being the most excited.
"Now, keep in mind that are," she recounted, "fifteen students. Ah good, the four Halliwell sisters, I take it?"
Prue spoke up, "Yes ma'am, sorry we're late."
"No problem, dear, at least you're here now," she says, "and just in time, too," she smiled, "anyway, as I was saying, the fifteen of you will enter and we will do this by last name. So, line up according to your last name," she encouraged.
The students all did so and, just as they finished, the doors to the great hall were opening.
"Enter, first years and new students," Albus Dumbledore, headmaster of Hogwarts, spoke up, "Don't be afraid," he encouraged with a smile.
All fifteen students began entering the great hall, memorized by the size of it all, along with being nervous over the sorting process.
Paige's POV
Oh god, it's my name? I'm going first then! Oh, no! What if I don't get placed in the same house as my sisters? Oh man, oh man, oh man! What am I going to do?
Okay, Paige. Relax. Breathe. Remember what Piper taught you. That's it.
Paige begins to breathe, calming herself down.
"Quinton Ava," someone calls.
Okay, I'm calm now. Breathe in, breathe out. In, out, in, out; that's it. There you go, Ms. Paigey.
She smiles, at Piper's nickname for her.
Since when did I start referring to myself as Ms. Paigey? Oh well.
"Paige W. Halliwell," a voice coughs.
From behind Paige, Phoebe pokes her, "Paige," she whispers, "You're next."
"Huh? Oh, right," Paige says as she steps up, sitting down on the stool.
The sorting hat is placed on her head.
"Hm," the hat speaks, "You're loyal, but you're cunning as well. You know a good lie when you hear it, child, but you're not one to hurt your friends or your family. Yet, you're ambitious. You want to better yourself. I see a jealousy in you too," the hat begins.
"Shh," Paige says as she avoids eye contact with Prue.
"Ah, a secret is it? I see you would never hurt her but, yes, a jealousy lurks underneath the surface. You love one another but, at the same time, you compete against her. Your cunning and resourcefulness plays in your favor," the hat nods, as if deep in thought, "Yes," it says, "I know the perfect house."
"SLYTHERIN!" The hat announces, causing cheers to erupt from the Slytherin table.
Paige shrugs, "Okay," she says as she runs over to the table.
She smiles at the young boy with white hair, who she sits next to, along with a pudgy kid.
"I'm Draco Malfoy, and that is Crabbe and Goyle," he points to the two boys.
Paige smiles, "Paige Halliwell," she introduces herself, holding out her hand.
The Malfoy kid shakes it, but only after a little bit of thought.
Phoebe's POV
Oh, great, Paige got Slytherin! I don't want Slytherin…bunch of creepy people in that house!
"Phoebe W. Halliwell," the woman calls.
Phoebe gulps, walking over to the chair and sitting down, as the sorting hat is placed on her head.
"Okay," the hat says, "You're defiant in ways, ambitious in others, but not as much as your sister; no. You're a bit of a scatter brain but, at the same time, you have a wisdom inside you yet untapped. A good bit of wit as well. You complain of school but love to learn, you're curious as a Cheshire cat. Yes, the perfect school for you," the hat says, "unless you do want Slytherin?"
Phoebe shakes her head, "I love my sister, I do, but I don't want Slytherin."
The hat nods sagely, "Very well then," it says.
"RAVENCLAW!" The hat calls out.
The Ravenclaw erupts in shouts, as Phoebe runs over to the table with a smile, "Hi," she says as she sits between two redheaded young girls; twins.
They smile at her and one speaks, "I'm Amara and that's Emara," she giggles, "What's your name?"
"Phoebe," Phoebe smiles, "Phoebe Halliwell."
Piper's POV
Oh god, I hope that hats clean! Piper thought to herself.
"Piper W. Halliwell," the woman calls out.
Piper, while holding Wyatt, makes her way to the chair and sits down, scrunching a little as the hat is sat on top of her head.
"Hm," the hat says, "You're valued around the house for your cleaning and cooking skills," it says, "You're rather fond of hard work, yet you have a layer of self-doubt that will keep you out of Gryffindor. You're known for your loyalty, although you have made mistakes, you refuse to let them keep you from your promises."
The hat nods, "You keep secrets when they must be kept, showing your loyalty, but I see a layer of braveness in you. Would you like Gryffindor?"
Piper looks shocked, furrowing her eyebrows, "Me? Gryffindor? No," she says, "I can't do that," she shakes her head, "I'm not brave enough," she moans.
The hat sighs, "Very well, Piper," and, if a hat can smirk, it would be doing so.
"HUFFLEPUFF!" The hat announces to the room.
The Hufflepuff table erupts in cheers as Piper carefully, but in a fast pace, walks down to the table. She sits next to two ladies. One with dark hair and one with blonde hair.
"Aw," the one with red hair says, "He's so cute!" The girl smiles down at Wyatt, "Yours?"
Piper nods, feeling a little self-conscious, "Yeah," she admits.
The red headed girl smiles, "Don't worry, we won't judge you here. I'm Lenette, by the way."
Piper smiles, "Hi," she says, "Piper Halliwell."
Prue's POV
Okay, all of my sisters are in different houses. How can I keep an eye on them? This is going to be a difficult school year, I think.
"Prudence W. Halliwell!" The woman calls out.
Prudence W, better known as Prue Halliwell, walks up toward the chair, and as the sorting hat is placed on her head, it sighs a little.
"Well," it says out loud, "You're a bit of a tough one," it admits, "You're loyalty for your sisters outshines the rest of your qualities but, at the same time, you could be placed in with the rest of the houses easily. You're cunning and ambitious, hardworking and loyal, witty and wise, but you also have qualities of the Gryffindor as well," the hat admits.
"Well," it says, "I'd like you to decide."
Prue shrugs, "No matter what, I can't be in the same house as all of my sisters," she sighs, "This just makes it harder for me to watch over them."
The hat nods, "Yes," it admits, "but you must let them grow up sometimes," it smirks, "Your courage is something you must find, dear Prudence, and your determination is already shining through. I see some chivalry as well, albeit in small doses, but it is there. How does the Gryffindor house sound to you?"
Prue smirks, "Okay," she agrees, "That actually sounds like a good idea."
The hat nods, "Indeed," it admits.
"GRYFFINDOR!" The sorting hat shouts out, causing the Gryffindor table to erupt in cheers.
Prue smiles, steadily walking over to the table, and sitting between a friendly looking girl and a red headed boy.
"Hi," Prue says, "Prudence Halliwell, but everyone calls me Prue," she smiles.
"That's Harry and Ron, and I'm Hermione," the girl says, "Nice to meet you," she holds out her hand, which Prue gladly shakes.
"Interesting," Albus Dumbledore says to himself, "Four sisters, four houses. Surely, this is not a coincidence," he smirks, "No, not at all."