(Thank you to maja5346 for updating)
Cassandra found herself staring up at her mom who was now slightly taller than her. "Hold on, why are you taller than me" she questioned confused.
"Because I made you two years old that's why" her mother giggled, "Sorry honey. Even if it's only by one year I wanted to be the older baby. But if you don't like it I can make you the same age as me" she replied.
"Nah its fine. I wanted to be younger than three anyway so everything worked out for both of us" Cassandra said turning her attention to her new smaller younger form. Like her mother her clothes had transformed into a toddler dress and lifting her dress to check underneath a thick diaper. Overjoyed to finally have her own set of padding Cassandra did a little celebratory dance of joy.
"Yay, I'm in diapers again! I'm in diapers again!" she chanted in childish victory.
Giggling at her daughter's antics the toddler asked with a smirk, "Happy now honey?"
"Very, thank you mom."
"You're welcome sweetie. Mommy's also very happy to have her baby girl back as well as being able to join her in toddlerhood." The three year old then noticed her daughter was fidgeting with her dress. "Something wrong?"
"No, I just realized I don't like that I can't see my diaper with my clothes on" Cassandra pouted a little.
"Oh is that all. I can fix that for you" she said as she concentrated and in a flash the dress was gone, leaving Cassandra in just her diaper like her mother. "Ooo that feels much better" Cassandra commented at being mostly naked save for her crinkly padding, her skin exposed to the air. Suddenly she could understand what her mom meant by being freer this way.
"And now since this is a momentous occasion for the both of us..." Concentrating once again there was another flash and two filled baby bottles appeared at the feet of the little girls. Bending down her mother picked one up while Cassandra did the same with the other. "...we should have a toast" she finished her earlier statement. Nodding Cassandra raised and knocked her plastic container against her mom's before sticking the rubber nipple in her mouth, holding the bottle with both hands. Sucking down the cool liquid inside she was delighted to find it was full of chocolate milk. Nursing the bottle greedily Cassandra drank every single drop of the tasty brown milk.
Her mother finished hers first and let out a loud satisfied burp that caused her to giggle afterwards. Cassandra on the other hand had trouble releasing her trapped air, to which the other toddler helped by patting her softly on her back until she burped too. Content with their tummies now full and tossing away the empty bottles the two regarded each other.
"Now what?" Cassandra asked.
Her mom smiled as she answered, "I was thinking of using the ring to wish us up a..."