Relating to my stepkids had always been difficult.  They always loved their ‘real dad’ more, even though they barely knew him.  It probably didn’t help that they were wolves and I was just a ‘mutt.’  So, when my youngest stepson asked me for the first time whether I wanted to play house with him, I said yes.
“I wanna be the daddy!” Todd said, raising his adorable 6-year-old arms above his head.  
“Hmm, then I should be ‘daddy’s friend,’ huh?” I said with a smirk.
“That’s silly!  You can be the doggy!” 
I blushed at the suggestion, but this was the first time that Todd wanted to do anything with me, so I said “okay.” Inwardly, I was rolling my eyes, but I got on my paws and knees and nudged him with my muzzle, panting.
“Hehehe!  Good boy!  Wait!  Puppies need collars!”
“W-well”
“Shhh!  Puppies can’t talk!”
I hushed, patiently waiting as he grabbed a black collar with strange markings on it that seemed to glow.  I thought nothing of it until he put it on me and I felt a strange tingle throughout my body.  There was a ‘tink’ and when I inspected the collar, a tag was there that I didn’t think was there before.  It read “Ruffus.”  Inwardly, I was fuming.  I hated when people intentionally misspelled my name to make a dog joke.  
Right around that time, Austin came around the corner and saw me with the collar, “playing house?”
“Mmhmm!  Rufus is playing the doggy!  I’m the daddy!”
“Haha, the doggy?  I think it’d be better if he was the baby.”
“Yeah!  I always wanted a baby brother!  Hey Rufus, you’re the baby now, okay?”
Inwardly, I groaned, but I nodded.  I reached my paws up to take off the collar, but I couldn’t find the buckle.  I stood up, then went to the bathroom to get a better look, so I could find it.
I looked in the mirror, twisting the collar every which way, but I didn’t see how he took it off.
“What are you doing in here, silly?  Babies don’t use the bathroom.  They use their diapers.” Todd said.
Just as he said that, I felt a strange tingling originating from the collar, and it seemed to glow brighter.  Weird.  “Hey Todd, where is the latch on this thing?  I’m trying to take it off.”
“Hehe, silly.  Why are you barking?  You’re the baby now.  You’re not a puppy.”
The collar seemed to dim a little, but I was confused by what he meant.  Was this a different game then the one I was thinking of?  “I said, where is the latch on this thing?”
“Ohh…I dunno.  I just put it on you.  Anyway, come on!”
I caught the glow of the collar once more in the mirror, and I thought nothing of it as I followed him to his room.  
“Lay down!”
I was a little embarrassed because he told me to lay down on his old changing table, but I complied, against my inner conflict.
“Austin!  Can you come help?” he yelled.
“What do you need help with, Todd?  I can help you.” I asked.
“Silly baby.  Babies don’t diaper themselves.”
“What!?” I asked, “Hold on, we don’t need to do that.”
Todd looked at me with his sad puppy dog eyes and I felt terrible.  This was the first time he wanted to do anything with me, and I was turning him down.  “O…Okay, Todd…I’ll be diapered for you…”
“Yay!” he exclaimed, just as Austin came through the door.
“Hey Austin…can you help me diaper Rufus?”
Austin burst out in laughter.  After almost a minute of hysterics, he gave me a wide grin. “I’d love to.  You’re going to have to get him out of his normal clothes first, though.” 
“You’re right!  Jeans and t-shirts don’t go on babies.  Take them off, Rufus!”
Grumbling inside, but smiling outwardly, I complied, stripping down to my underwear in front of the two wolves. 
They both stood around waiting.  “Well?” Austin finally asked.
“Well what?”
He laughed.  “You have to take the underwear off to get in a diaper.”
“Isn’t this just pretend?  Can’t I just wear the diaper over my boxers?”
“No!” Todd huffed.  “Babies don’t wear underwear.  Babies wear diapers.”
Against my better judgment, I stripped my last protective layer and blushed a deep red as their curious glances inspected my malehood.
“HA…HA…” Austin burst out into hysterics, once more.
“Austin told me that my wee wee is supposed to get bigger when I’m older…but yours is…smaller…” Todd said, confused.
I wanted to put my clothes back on and just call it off, but I couldn’t bring myself to do it.  I covered myself with my paws and looked to the side.
“He’s not playing baby.  He really IS a baby!” Austin cackled.
“Can we…Can we just get on with it, please?”
It took him a few moments, but Austin calmed down.  “Fine, fine.  Hop up on the changing table…baby!” 
I cast an annoyed glance at him, but got up there anyway.  I don’t think they had diapers that would fit me anyway.  They’d probably just wrap a towel on me or something.
“Here we go,” Austin declared, grabbing a crinkling mass from under the counter.  It was a Barney-printed diaper from when Todd still wet the bed that would in no way fit me and they would find out soon enough.  I looked away.  I couldn’t stand to see a 13-year-old diapering me as his little brother watched.  Austin muttered something under his breath, and I cried out in surprise as cold baby powder fluffed onto my crotch.  When I looked at him, he had the biggest grin on his face.  I looked back away, not wanting to get in a staring match with the rebellious teen.  “Aaaannnd-done!”
“Wait, what?” I asked.  I looked down at my crotch, and surely enough, there was a Barney-printed diaper there.  How did he?  It looked huge on me…bigger than when he took it out of the drawer…
“Yay!” Todd exclaimed, “I have a baby brother!”
“You sure do,” Austin said, tussling my hair, eliciting a low growl from me.
“Come on, baby bro!  It’s time to put you to bed!”
“Huh?” I asked…It was noon.  There was no way that he expected me to sleep…  Still, I followed him off the changing table as he led me to his old crib.  We only kept this thing because I wanted kids with Linda eventually.  Little did I know that it would come back to bite me like this.  
I felt a pat from behind and Austin winked at me, “Come on, BABY bro…get in your bed.”
I sneered.
Todd pouted, “you have to listen to Austin too!  He’s your big brother too, now!”
I got into the crib, still annoyed at the teenage punk.  Thankfully, it was big enough that I could fit in it, but just barely.   ‘I’ll pretend to sleep until Todd doesn’t want to play this game anymore, then maybe we can do something else’ I thought to myself.
“Oh wait!  Babies sleep when they suck on their pacifiers!” Todd cried out, rummaging through the changing drawer until he pulled out a small blue pacifier.  Reluctantly, I put it in my mouth and began to suckle, eliciting a chuckle from Austin.  That tingly sensation coursed through my body again, and I began to feel very heavy.

I opened my eyes to see Austin standing above me.  “Wakey wakey, baby bro.  It’s time for your changy.”
“Ha ha…Very funny.” I drolled.  “Where’d Todd go?”
“He went to sleep.  It’s 8pm.  He’s tired from watching his baby bro.” Austin pointed to the other corner of the room at a sleeping Todd.
“Yeah, right.  I literally just closed my eyes for a second.  Are you guys playing a trick on me or something?”
“Look out the window”
I got up, feeling a little weird as I waddled towards the blinds, peeking beyond them.  It was dark outside.  How…
“Now, it’s time for your change, baby bro.”
“No.  I’m tired of your shit, Austin.  I was playing pretend with Todd because he was finally wanting to do something with me and that made me feel good.  You just want to make fun of me for not being your dad.  If Todd isn’t here, then I’m done playing games.”
Austin growled at me, “Well…I’m tired of your shit!  You’re not our dad!  Our dad is cool!  For instance, he made that collar for me to use on you!”
I reached up to grab the collar.  It wasn’t there anymore.
“That’s right!  It’s permanent now.  I was surprised when Todd had put it on you because I was waiting for the perfect time to keep it on you for a few hours so you couldn’t cut it off!  Turns out, my little brother did it for me.  It sucked that he was the only one who got to issue orders to you, but guess what?  He said that you had to listen to me too!  Now sit down and shut up!”
I was about to grab him and spank him for talking so rudely to me, but I was surprised when I found myself sitting down, my crotch suddenly very cold.
	“Feel that?  It’s your wet diaper.  Todd said that babies use their diapers and you’re a baby…That is, unless you think you just wet yourself in your sleep.  I’d believe it with that baby dick of yours.  Heck, you’re not even taller than me.  Now, since you’re sick of my shit, I think I should wake Todd up and tell him about how you wet your diapers.  Think that will make him respect you?”
	I shook my head, angry, confused, and terrified all at the same time.
	“I can’t stop you from wetting yourself when you’re in diapers and considering that he said you couldn’t use the bathroom, you’re probably going to be in diapers a lot more often.  So, here’s what’s going to happen.  My mom is off-limits to you.  You can’t have sex with her, feel her up, or do anything even remotely sexual with her.  Period.  I’m the alpha when my dad isn’t here and he’s the only one that gets to be with my mom.  But if I make you break up with her, she’ll just find someone else.  So, you’re going to be a good little guard dog.  A good little chastised guard dog…Ruffus.”