From the report from her fans who were at the stage…

During the last greeting of the show (= Setlist), Kojiharu appeared on the stage, saying “Wait a moment!”. Then as Namida Surprise is playing in background, someone appeared pushing a cart, on which a birthday cake was put. As I watched her face carefully, I found she was Yukori (Yukari Satoh:former member of AKB, SDN).
Though Kojiharu was supposed to do a MC role, Yukori did almost all MCs.
Yukori read her letter to Mariko by herself…
Mariko-sama had watery eyes, as she listened to the letter… (’ー‘)
After that, Mariko-sama read her letter to fans.
At the last moment, Mariko-sama let Jurina, who were at the show as an audience, come onto the stage, then Jurina made a brief greeting to fans and Mariko-sama, then she briskly left the theatre. (She can’t work in late at night because of her age)

Yukori, Mariko and Kojiharu (Movie)
Cast:  Aika Ohta, Haruka Katayama, Shizuka Ohya, Mocchi, Sashiko, Mariko, Aki Takajo, Harugon, Tisato Nakata, Acchan, Ami Maeda, Natsumi Matsubara, Yuuka Tano, Rina Izuta, Natsuki Kojima, Tom Muto

This was the first Revue in AKB theatre for Acchan, and 2nd for Sashiko.

Akicha (Aki Takajo)
Today was the day of Mariko-sama’s Birthday Celebration Festival!!
I was so moved by Mariko-sama’s letter.
Happy Birthday Mariko-sama!
I am wearing Birthday-T in Bocchi meeting. (Bocchi = single = living separately from their family)

Acchan, Harugon
Harugon, Acchan
生誕祭ありがとうございました\(^o^)/にゃろとじゅりな、そしてゆこりまで(笑)きてくれてビックリしたーーー!!! なんかビックリサプライズな生誕祭でした(笑)ありがとうございました( *`ω´) 皆大好きやあーー(`_´)ゞ

Thank you so much everyone for holding such a great festival for my birthday. I received big surprises! Nyaro and Jurina, then even Yukori(笑) came over the stage! It was like… a big surprise birthday celebration festival(笑) Thank you( *`ω´) I love you allーー(`_´)

Nyaro=Kojiharu, Jurina, Mariko, Yukori
Incredible gift from her fans with Maripanda on the top!!! 
Read more on Marik-sama’s birthday celebration party
Jurina Matsui Made Surprise Appearance At Mariko’s Birthday Celebration Festival In AKB Theatre