Secret Family centers around Po, from Kung Fu Panda, as he seeks out his long lost brother, Assef, the antagonist of the Kite Runner novel.
In the introduction, Po learns that he is adopted, and that he has a brother, who is both human and Aryan. Po travelts to Afghanistan. Assef shows up and introduces himself as Po's brother. He informs Po that for some reason, their mother managed to give birth to both a human and panda baby, and that the two were separated, for reasons unknown.
A few days later, Po is staying in Assef's home, and the two communicate regularly via text messaging. Po has taken to cross-dressing, and develops an infatuation for Assef's friend, Kamal (or Kman as he is now known.) One day, while out walking, Kamal is taken captive by Hassan and Amir, prompting Assef, Po, and Wali to go on a rescue mission.
While in battle with Hassan, who has somehow managed to get hold of "machine gun kites", Po reveals that he is pregnant with Kamal's child. He goes into labour as they are been shot at by Hassan and Amir, and gives birth to a yellow, square baby, who he calls Spongebob. Po is briefly killed by a stray bullet, but somehow mangages to come back to life a mere minute later.
As time passes, Po, Assef and Spongebob are now living happily in Assef's home. Po is a neglectful mother, however, spending most of his time on makeup and crossdressing, and leaving Assef to care for his nephew. One day, while spending quality time with his son and brother, Po has a nightmare in which Assef, Wali, Kamal, and Spongebob are brutally killed by Hassan and Amir.
This prompts them into escaping to America. Along the way, Wali randomly transforms into a woman, Waldina, and starts a romantic relationship with Assef. Upon arriving in the US, Po loses Spongebob, a fact that it falls to Assef to point out. In a fit of self-rage at having lost his baby, Po turns into the Incredible Hulk, delivering a fatal beating to Kamal.
While in hospital, Po notes that Assef has yet to add him as a facebook friend. Assef is apologetic and promises he will do so as soon as Spongebob is found. A doctor informs them that in order for Kamal to live, someone will have to breakdance on top of his body. Po willingly obliges and Kamal is inexplicably ressurected. Assef then appears, with Spongebob in his arms, and the happy family leave the hospital.
Time passes yet again, and Po is now living happily with his brother and the rest of his new family. Po takes his baby out for a walk with Assef and Waldina. He gets excited as they feed the ducks, and bounces up and down frantically. Spongebob falls from his mother's arms, and into the nearby lake.
One of the ducks then reveals himself to be Hassan. Hassan threatens that he will kill Spongebob if Po does not come with him. He takes out a gun and shoots Waldina in the chest, killing her. Then the story inexplicably ends.