Ananya Kolvankar

is the title character and youngest of the Singh siblings, after Sunny. She is mostly portrayed as being happy and seldom cries, although she does, though rarely, get upset for various reasons. Nikki can also be mischievous at times. Nikki is apparently closest to her older sister, Dolly, who is currently creating a video diary to assist Nikki as she progresses through life. Many of the Singh family's adventures revolve around Nikki, and cause her three older siblings to be constantly taking care of her. Her older brothers, Rohan and Sunny, are often seen using Nikki for their own benefit, although Rohan shows that he cares about her deeply. However, Sunny seems to dislike Nikki the most although, in some episodes, he is seen being quite fond of her. Hemani thinks of Nikki as the perfect baby, being cute and all that. Sheena Bajaj played an older version of Nikki in "Bye-Bye Video Diary", in a dream sequence that shows what Dolly fears if Nikki does not receive the video diaries, Nikki might act badly, quit school, run away with her juvenile boyfriend, and resent Dolly. It was revealed in "Nikki is 1", that it was Dolly's idea to nickname her Nikki. Nikki was seen having short hair, usually tied up like a bun in the first season, but as she grew older, had longer hair in a ponytail or pigtails. Nikki speaks more often in later episodes of Season 2 and in Season 3. She shares a birthday with Singh's family's fifth member and said, "I like this present" when he was born. In Season 3, her personality begins to develop, as she is seen as sneaky and mischievous, such as pretending to like a doll Hemani bought for her to like him, but then throwing it away when she wasn't looking, and also telling Hemani's "friends" what she really thinks of them, causing her to lose them all. Her personality is most like Sunny. In Good Luck Charlie, Nikki is the equivalent of Charlie Duncan who is played by Mia Talerico.