In the prologue, Chat finds out Ladybug is mute. He thinks she is amazing anyway. He goes home and detransforms.  Afterward, Adrien smiles and thinks, poor Ladybug can not talk.

    "Plagg for a mute person Ladybug is cool.  I mean it she fought rather well." Adrien says.

  "This reminds me of the blind ladybug who was around once.  It was a long time ago, but she was something." Plagg says.

Plagg says, "I feel sorry for the new ladybug too it can not be easy for her to communicate without speech." 
  

"Plagg, you have a great memory for a kwami. It sounds like you are super smart." Adrien says.

     Dear Journal,

      Today, I had to fight against the villains Anti bug and The Bubbler. I had help from Ladybug, but she never said a word.  After the fight, I found out she is mute due to a note she scribbled for me on a sheet of paper. 

    I admit this took me by surprise. It has me feeling rather sorry for her. I can not help, but wonder how she was given such a huge responsibility without the ability to talk.  

     I think she is awesome, the way she stood in front of the villain and took her earrings. Then, later she caught the akuma. Also, the way she caught the second akuma once Queen Bee had broken the wand.  I admit it was impressive.  

    As Chat Noir I admire her but have no idea what she looks like as a civilian.  I hope to meet her in her other form someday. Perhaps, we could become great friends. I could always text her since she can see and hear just fine.

    Plagg, my kwami notices she is special as well.  He sure is a smart one.

     _Adrien Agreste

Meanwhile, with Ladybug who is back in her home and in her civilian form, Tikki hands her some paper and a pen. She smiles at her and thinks, she might be unable to speak, but she is still doing so well today.

   Tikki wrote on the notepad  the following note:

    Marinette, you did an excellent job on your first day as the new bug hero!  This was amazing!  I  once had a blind ladybug and even a crippled one.  Yet even as good as they did, you surpass them all.

   Do not ever give up!   No disability should keep you from being who you are meant to be a hero.  

   Some of the past ladybugs were boy's and a few of the past Chat Noir's were girls.  No matter the Ladybug they all had the same things in common:  They were all kind, compassionate, and willing to fight alongside their partner Chat Noir, or in some cases Kitty Noir, or even Ladynoire.

   It is an honor to be your friend and kwami.  I know I might have to jump into your earrings on my own, but it will be okay.  Besides,  you can always use a special signal for me if you need me for anything.

   Master Fu, the guardian of the miraculous promises to work on a cure for you. He did say even if it works there is no guarantee it will be in both forms.  

   In other words, if it does work you may be able to speak as Ladybug, but still have no speech as Marinette. Then, there is a possibility it might not work at all, or you will talk as Marinette and not as Ladybug. The results are uncertain for now.

   Master Fu says when you are ready he will give you some of the formulae to try. 

However, it has the following side effects:  it can cause dizziness, headaches, and maybe some fainting spells. It might cause mood swings and could even result in death if you took to high a portion of a dosage.  This is why he recommends you take it in small form.  

   It should be ready soon.  If you feel nervous and uncomfortable with the idea of it, you may refuse the formulae when he finishes it.

  The current Chat Noir is rather kind which is good news because some of the past ones were rather cruel.  He is a bit of flirt, but he seems to care about you. This is good because he will do all he can to protect you.

  Thanks so much for all you have done, and will continue to do for us, Marinette or should I say Ladybug?

 Sincerely, Tikki

  Marinette smiles as she reads the note. She is glad to have a new friend. She shakes her head and thinks, correction two new friends.

   Marinette's POV:
    Who is this Master Fu Tikki talks about anyway?  Have I met him or will I meet him soon?

   It might be dangerous but as one of the heroes of Paris, I think it is worth it to try the formulae. 

     Tikki's  POV:
  She wonders what Marinette thinks about her new job, Chat, Master Fu's formulae, and her life in general.

    Tikki flies over to Marinette and sits on her shoulder. She thinks, well this has been one fantastic day.