Kiara and her father Simba are shown to have a loving father-daughter relationship. Although she won't admit it, she loves being "Daddy's Little Girl", as Kovu once called her. Some point after that fateful day whereby she met Kovu, Kiara became more accepting of her destiny as the Pride Lands' future Monarch. Simba taught her the importance of family, unity, and destiny in their father-daughter duet song, We are One. She now enjoys learning about the importance of ruling from him and is determined to be a great Monarch when her time comes. She is in a unique position whereupon she is the first female cub to inherit Pride Rock and will assume the throne as the Pride Lands' first queen regnant (at least the first to do so in several generations). While she looks forward to becoming queen, deep down, she will always be "Daddy's little Princess." She loves her father deeply and becomes worried when he is hurt, as seen when she stays by his side the whole day when he is sick.
Years later, Kiara convinces Simba to accept Kovu and the Outsiders, into the Pride Lands, and Simba gives Kiara and Kovu their blessing to marry, and they soon become Simba's successors to Pride Rock.
The two are shown to have a loving mother-daughter relationship, and Kiara enjoys learning about the importance of hunting and tracking from her. She trusts her daughter completely and, unlike Simba, lets her do things on her own. Nala always worries for her daughter whenever she's in danger, and has faith in her, knowing she can and will be a good future queen.
Kiara and her younger brother Kion have a typical, yet loving sibling relationship. Although the two squabble occasionally and don't always see eye to eye, they do hold affection for each other but are prone to sibling rivalry occasionally. Sometimes they'll have a "sibling fight" where they end up tackling each other. Over the course of the series, they appear to be on better terms with each other. In The Trail to Udugu, Kion and Kiara learn to work together to find their mother, Nala.
The two briefly play with each other and work together well in The Underground Adventure. She also sees Kion's duties as Lion Guard leader more important than ever, now that Scar has returned and became annoyed when her brother was called for a minor emergency.
Kiara becomes concerned for her younger brother when he gets bitten by Ushari during the final battle against Scar in Battle for the Pride Lands. When she learns that Kion can seek help at the Tree of Life, Kiara and her parents wish for his safe return. In Return to the Pride Lands Kiara and Kion talk about Rani and how Kion misses her. Kiara says that maybe Kion can go back to the Tree of Life one day.
Scar is Kiara's great uncle and we know that Kiara is not on Scar's side and it doesn't look like she will ever try and be like him. But she is aware of Scar's return and helps her family in calming down the worried Pride Landers.
At some point before her brother's birth, Kiara met Kovu and quickly became friends with him, but was separated by their feuding parents, where Kiara was taught to accept her destiny as Queen of the Pride Lands, whilst Kovu was trained to become a cold-blooded killer. In Lions of the Outlands, Kovu became excited when Kion hinted towards a possible reunion with her in the Pride Lands.
In Season 3, Kovu has become Kiara’s mate and consort. After Kion left Pride Rock, Kovu grew up and infiltrated the pride, but unfortunately for Kovu's mother, Zira, they both fell in love and later worked together to unite Simba's Pride and the Outsiders, before becoming mates and future rulers of the Pride Lands.
Mufasa is Kiara's grandfather. Although he died before she was born, it's likely that Kiara is aware of the former King and has great respect for him. Kiara sees Mufasa in Return to the Pride Lands and appears to be happy to be seeing him.
Vitani used to hate Kiara due to the feud between their prides. However, after Kiara explained how both prides should come together, Vitani was the first to understand her wisdom and switched over to Simba's Pride, which convinced the other Outsiders to do the same. They became sisters-in-law after Kiara married Kovu. The two have since formed a strong friendship. When Kion and his Lion Guard returned from the Tree of Life and fought Vitani and her Lion Guard (due to not knowing that the war between the prides had ended) Kiara, without hesitation and risking serious injury, jumped in front of her brother before he could use the roar of the elders on Vitani and her guard. This shows that both Kiara and Vitani completely accept each other like family and are willing to defend each other without hesitation. Kiara is also shown to sympathize with Vitani and Kovu's sadness over their mother's death. Kiara cheered for Vitani when she became the official new leader of the Lion Guard.
Zira is Kiara's mother in law because of her marriage to Kovu. When Kiara and Kovu united the Outsiders and the Pride Landers as one, Zira refused to make peace with her and Kovu as revealed in Return to the Pride Lands.
Tiifu, along with Zuri, is one of Kiara's best friends.
Tiifu was very concerned and worried when Kiara became trapped in a stampede, set by the evil hyena Janja and his clan and was relieved when her friend was rescued. In Can't Wait to be Queen she and Zuri became Kiara's Royal Advisors during her reign as temporary queen. She was incredibly supportive of her friend during this time. Much like Zuri, Tiifu also likes to make sure that Kiara looks her best for important events, such as for example the Royal Buffalo Wallow. She has shown to be incredibly grateful towards Kiara for saving her in Baboons!. Tiifu also accompanies Kiara on her hunting trips, as seen in Return of the Roar, where she is once again very supportive and enthusiastic about working together with her. Tiifu refers to Kiara as her 'leader'.
Tiifu is very overprotective of Kiara, more so than even Zuri, and becomes jealous when others become close to her, as seen in Fuli's New Family.
Kiara is caring and comforting towards Tiifu, soothing her fear of the darkness by staying by her side when they escape underground in The Underground Adventure.
Zuri, along with Tiifu, is one of Kiara's best friends.
Much like Tiifu, Zuri is a supportive friend to Kiara, who believed in all of her decisions, when she was placed as one of her royal advisors in Can't Wait to be Queen. She has also stuck up for Kiara when others doubt her. Also, like Tiifu, Zuri is always up to help Kiara look her best for every occasion. She has shown to be incredibly grateful towards Kiara for saving her in Baboons!.
She is less enthusiastic about their hunting trips than Kiara, though she attends them seemingly only for the sake of being her best friend. Also, she dislikes hunting and getting dirty.
The cub also dislikes it when someone threatens her position as Kiara's royal advisor, as seen in The Rise of Scar.
Kiara is shown to have a good relationship with her younger brother, Kion's best friend, Fuli. In Fuli's New Family she hunts alongside Kiara and seems to be on friendly terms with her. She even saved the princess from falling into a sinkhole in Bunga and the King.
Kiara is shown to have a good relationship with her younger brother Kion's best friend, Bunga. At first, she was skeptical of the honey badger, who she believed was a terrible choice for Kion's Lion Guard. She seemed to be disgusted by his stink when he used it to save her in Return of the Roar. Though she is often annoyed by his bad odors, she did not mind when Bunga used it to save her from being trampled by gazelles. After being saved by him, she appreciated Bunga much more.
Ono seems to have a good relationship with Kion's older sister, Kiara. In Can't Wait to be QueenOno is very respectful towards Kiara. Ono was temporarily in charge of the Morning Report when Zazu went with Simba and Nala.
Kiara likes to work and talk together with Makini, as seen when they try to help the elephants find a new source of water. Makini does care for Kiara, which is proven true when she tells the guard that the hyenas had kidnapped her and she thinks it’s her fault, although the guard assures her it wasn't her fault. None the less the two seem to be friendly towards each other.
Kiara becomes good friends with Dhahabu when she comes into the Pride Lands and even gives her a tour. She has great respect for the zebra queen and makes sure that she feels comfortable while she was visiting the Pridelands in The Queen's Visit.
Kiara was willing to give Janja the benefit of the doubt in Can't Wait to be Queen, hoping that an arrangement could be made that would stop the fighting between them and the rest of the Pride Landers. However, upon learning that Janja had tricked her, Kiara never trusted Janja again.
Chungu helps Janja with nearly every evil scheme. He along with the rest of Janja's Clan attempt to murder the princess inCan't Wait to be Queen, only to be stopped by the Lion Guard. In The Rise of Scar, the hyenas attack her and Makini and under Janja's orders, he kidnaps the princess and carries her all the way into the Outlands as part of Janja's plot to summon the spirit of Scar. Then, he throws her in the steam vent by the Outlands Volcano.
Cheezi helps Janja with nearly every evil scheme. He along with the rest of Janja's Clan attempt to murder the princess in Can't Wait to be Queen, only to be stopped by the Lion Guard. However, he is disappointed that Kion and Kiara were not fighting each other showing how much he enjoys violence. He attacks her in The Rise of Scar when she and Makini were strolling around the Pride Lands as part of Janja's plan to summon the spirit of Scar.
Nne helps Janja with most of his evil schemes. He along with the rest of Janja's Clan attempt to murder the princess in Can't Wait to be Queen, only to be stopped by the Lion Guard. He attacks her in The Rise of Scar when she and Makini were strolling around the Pride Lands as part of Janja's plan to summon the spirit of Scar.
Tano helps Janja with most of his evil schemes. He along with the rest of Janja's Clan attempt to murder the princess inCan't Wait to be Queen, only to be stopped by the Lion Guard. He attacks her in The Rise of Scar when she and Makini were strolling around the Pride Lands as part of Janja's plan to summon the spirit of Scar.
Mzingo manipulated her into believing that if she met Janja at Broken Rock at sunset, that he and Kiara could make things work (really part of Janja's plot to rule the Pride Lands) for the Pride Lands. Kion, however, scolds her for trusting him because he knows that he along with Janja are villains who cannot be trusted regardless of what they say. Kiara later finds out that what he said actually was a lie. However, in Return to the Pride Lands, Kiara forgives Mzingo for his previous actions.
Kiara used to dislike the lions when they were part of Zira's Pride. However, when Zira completed her journey through the Circle of Life, they joined Simba's Pride. Kiara becomes on good terms with them.