Original characters by first chapter appearance:

Chapter 1
Saori Uzumaki- Naruto and Sakura's oldest child, a daughter, three years old in the chapter

Chapter 6
Harumi- mischievous, perverted girl on Sakura's Genin team, 13 years old in the chapter

Eiro- quiet, prudish, but kindhearted boy on Naruto's Genin team. 13 years old in the chapter

Isao- perverted, gregarious boy on Naruto's Genin team. 13 years old in the chapter

Kitomi- romantic girl, and a budding writer on Naruto's Genin team. 13 years old in the chapter

Chie- naive, slightly tomboyish second girl on Sakura's team, member of the Inuzuka clan, a cousin of Kiba and Hana. 13 years old in the chapter

Manabu- member of Sakura's Genin team, he hero worships Naruto. 13 years old in the chapter

Chapter 8
Chimaki (mentioned)- Gaara and Matsuri's oldest child, a son, same age as Saori (newborn at this time)

Dasuke- Shizune and Aoba's son, two years old in the chapter

Chohiko- Ino and Choji's son (infant at this time)

Naoto- Hinata and Kiba's oldest son, (2 1/2 years old at this time)

Jiro- Hinata and Kiba's second son, same age as Saori

Chapter 9
Dengyo Isshi- (deceased, mentioned) oldest member of the council during Tsunade's era as Hokage, died of old age (90's) shortly before Naruto became Hokage, allowing Tsunade to take his spot on the council at the next election, a few months after Naruto became Hokage. He was an ally of Danzo.

Two young Root trainees - rescued by Sasuke and Sai, who become the boys guardians- Older boy named Akio, younger Nobu, then aged 8 and 10.

Midori Katoshima- a 17 year old Anbu member, subordinate to Sasuke, who is like Naruto of mixed Whirlpool blood, and shows her whirlpool father's family bloodline trait.

Kei Uchiha- (deceased, mentioned) Sai's secret father, first cousin to Sasuke's mother Mikoto. Never knew he had fathered an illegimate child, was engaged to another Uchiha cousin when he died in the kyubi attack on Konoha

Takemi Yosano- artist, mother of Sai, died of an illness when Sai was five years old.

Chapter 12
Haruki Uzumaki- Naruto and Sakura's son (infant at this time)
Tsuru- apprentice nurse, 14 years old in the chapter

Chapter 15
Cloud country's Daimyo and his wife- a young naive, idealistic couple who want Cloud to ally with Fire

Chapter 16
Airi- Shino's wife
Shinzu- Shino's son, 2 years old in the chapter

Chapter 21
Ayane- Naruto and Sakura's younger daughter and third child (infant at this time)
Taizo-Hinata and Kiba's third son, same age as Haruki
Shikami- Shikamaru's and Temari's daughter, same age as Saori
Shikaru- Shikamaru's and Temari's son, same age as Haruki
Nui- Neiji and Tenten's daughter, same age as Haruki

Chapter 22
Kameyo- a retired ninja in her 90's who is a great storyteller.
Shou- Neiji and Tenten's son (obliquely mentioned, Saori's age)
Ishio- Hanabi and Rock Lee's older son (obliquely mentioned, one year younger than Haruki)
Denbei- Hanabi and Rock Lee's younger son (obliquely mentioned, one year older than Ayane)

Chapter 24
Maya- an Academy student, then 12 years old