Phineas and Ferb: Candace in charge (Private with TheNameless)
 

Candace had finally had enough of her brothers antics. She had never been able to bust them up to this point. So she devised a plan to punish the boys instead of failing to bust them. After a week of planning and lots of shopping she had finally had all the items she needed. Her punishment for the boys was to baby them to the fullest extent. This meant their wardrobe would change, they would be put back in diapers, be bottle fed, etc. She even thought about limiting how they walk and talk. Candace had all the items to baby the boys for quite a while. Thankfully she had talked them into building a nursery for someone of their size. She called the boys into the nursery and put her best sad face on. Once Ferb entered with his brother and saw candace he was a bit confused and hugged her.

Phineas came in with Ferb and joined in on the hug. He too also was a bit confused.
Phineas: Hey Candace, what's up?

"You know boys...i really miss the good old days" Candace said. "I miss when you guys were babies" She added. "I want my baby brothers back for a while" She said. "I had you guys build this nursery for both of you" Candace admitted. "Will you guys be my baby brothers again? Pretty please?" She asked, patting the changing table. Ferbs face turned bright red as he looked at Phineas and then at Candace. "That...doesnt really sound all that bad, i think ill give it a try." Ferb said.

Phineas: Of coures, after all it would be great to be a baby, or atleast treated like one. I'm just surprised you came up with this nursery design so well. Even adding in a mental ray that give anyone a regressed mind if they want to have a full baby experiences.
As the Boys get ready to be diapered, Phineas then thought to as one thing that seemed suspicious in Candace's request.
Phineas: Though one thing I don't get is what the baby punishment for?

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Sorry had a busy day yesterday, I still quite new at this. I added a reference in the text and gave us the way on how candace makes sure that the boys under her thumb for sure.

"Punishment? Why would i ever punish you guys?" Candace replied. She got Phineas and Ferb stripped naked and placed them on the changing table. In no time the boys were put in very thick crinkly diapers with cute baby designs on them. She then put soft snap crotch onesies on them and clipped pacifiers to each.