The character of Paddy from Colleen McCullough's novel The Thorn Birds is arguably most like Baba in The Kite Runner. He also shares some pivotal similarities with Tariq from A Thousand Splendid Suns.
Paddy Cleary can best be described as:
...a hardworking, simple, good hearted, and perpetually bewildered man who dies early. A man who believes in old ways and in keeping in one's place, he cannot afford for his children to remain in school, needing them on the home place to work; he believes as well in the strict delineation between woman's work and man's work. Both policies are hard on Fee and her eldest son, Frank, and this creates a rift between father and son. He is a character who imbues in his children the capacity for hard work and love for the land; an Irishman, he fled to New Zealand, where the novel begins, after killing an Englishman.
From this information, it is clear that Paddy shares some qualities with Baba. While Baba is wealthy and Paddy is poor, both men see the value of hard work and the importance of family loyalty.
Both men additionally have emotionally restrained relationships with their children. In Paddy's case, he finds himself experiencing tension with his eldest son, Frank, as the two compete for Fiona's attention. In Baba's case, his sense of moral superiority alienates Amir and makes him seem like a towering presence.
Both Paddy and Baba have children responsible for atrocious acts. Like Paddy's son Frank--who ends up serving a thirty-year sentence for killing someone in a fight--Baba's son Amir ends up being complicit in a crime as well when he fails to stop the beating and rape of Hassan by an older bully.
Both reveal critical information relating to their roles as fathers. Paddy winds up admitting that Frank is not actually his biological son, while Baba reveals that Hassan is actually his biological son. Both boys are "bastard" children born of affairs.
Both travel far from their homelands, with Paddy migrating from Ireland to New Zealand and then to Australia, and Baba migrating from Afghanistan to California.
Both committed transgressions of their own: Paddy killed a man in his home country, while Baba cheated on his wife.
Finally, both men die under tragic circumstances; Paddy perishes in a lightning fire, while Baba passes away from cancer.
We can also see how Paddy resembles Tariq in terms of their agreement to parent children who were not biologically their own. When Tariq returns to Laila after their long separation, he agrees to take care of Zalmai, even though the boy is the biological son of Rasheed. In much the same way, Paddy agrees to marry Fiona despite the fact that she has already given birth to the child of another man.
Paddy and Tariq are both also arguably similar in their disposition. They both have faced many trials and acted out against the law--as previously mentioned, Paddy killed a man, while Tariq was imprisoned for smuggling hashish--but both are inherently good-hearted individuals.