Clean and in jeans and a t-shirt Trent went back down into the living room. Thinking about the dress he'd need to wear it anyways.. and it's not like he could take it off at school and then come back as a guy, he'd need to carry too much clothing and his commute was less than half an hour, and someone was always home... Trent sighed and grabbed the dress and went downstairs where his mom was.
Trent said "Mom I got something to show you."
Mom asked "Was it about that thing you were wearing?"
Trent said "Yeah, remember that bet I made with Alice?"
Mom responded "Sure, your sister told me. That was hilarious wh-"
Trent said "Anyways we went to the magic store and got a random item more or less..." Trent was now in the living room with the dress in his arms and said "That item was this dress."
"...so then... would you put it on?"
Trent asked "Huh?"
"Well, your going to wear that to school so i'd at least like to see what you look like in it, and since it's from that store it'll do something right?"
Trent sighed and just put the dress on over his clothes, and the magic worked on Trent's body somewhat easily. Trent said in her female voice "Well, this dress makes me a girl. It'll stay that way till an hour after I take this thing off."
"Very least you look ... pretty. Although the dress would seem kind of off in high school." mom thought for a second and wondered out loud "Wonder if Claire will get that big..."
Trent feeling a bit embarrassed said "Well if you'll excuse me i'll be waiting out the hour timer." and then took off her dress to reveal her shirt had turned into a blouse of the same color and the jeans turned into skinny jeans really showing her curves. Plus the underwear changed as well.
"Well that's convenient."
"Well i'd hope it'd be a little convenient, after all it's magic!"
The front door to the house opened and Trent's 10 year old sister Claire came in and said "I'm home!" She dropped off her bag near the front door, took off her shoes and went into the living room and asked "Oh hi miss, are you Trent's friend?"
Their mother giggled as Trent said "No, I'm Trent. When I lost that bet I had to wear this dress at school for a week which made me this young woman."
Claire said "Oh so that dress turns men into women?"
Trent said "...not exactly, here try it on." then tossed it to his sister. Claire decided to try it on and in a few seconds the little sister in her older sister's clothes started to stretch and grow stopping only an inch shorter than her older sister. Then her figure started filling out in a similar way.
Claire cupped her boobs and said "I've got boobs!"
Trent said "Indeed, as do I, and mom does as well." Trent looked around and then continued "...where is mom anyways?"
Their mother back with a Camera said "Can I have you two young women turn over here so I can get a picture or two?"
After a long session of taking pictures, and trying on different dresses Trent asked "Hasn't it been an hour yet?"
mom looking at her watch said "Actually it has... the dress isn't permanent is it?"
Trent thought and said "Claire take off the dress and we'll see in an hour..." Claire didn't like the thought of losing her boobs but took off the dress, and her old clothes properly fit her current body thanks to the dress magic. An hour later and Claire shrank back down to her prepubescent self, and Trent's dick grew back. Trent coming out of his room said in his fully masculine voice "Well that worked, I guess as long as the dress is being worn by someone everyone effected wont change back... Now excuse me as I go prepare for school tomorrow."
Little did Trent know that when he got to school the next day...