Anyways my theory is that Kopa and Kovu meet when they’re cubs (let’s face it, the Pridelands and the outlands are practically next door neighbours; they were bound to meet sometime) And they stay friends though their childhood - meeting in secrecy muct to Simba’s discouragement. The relationship between Simba and Kopa becomes more and more strained as the Prince matures to the point where Kopa is spending more time with the Outlanders than the Pridelanders (Zira is more than happy to harbour a member of the royal family who is open-minded towards Scar and his rule and gladly accepts him as Kovu’s friend (this is just my opinion of course)). Simba scolds his son whenever he actually sees him for associating with them and soon enough Kopa leaves to join the Outsiders. When the betrayal of his Son become too much for Simba to bear he confronts Kopa and tells him that he refuses to fight against his own blood. This leads to Kopa leaving the Pridelands and Outlands all-together to become a rogue much to Kovu’s horror but Kopa promises that they will meet again (Zira wouldn’t let Kovu leave with him as he still has a lot more Simba-Killing-Training to master). Eventually Kopa returns to the Pridelands after hearing that the feud between Pridelanders and Outlanders has been resolved and receives an apology from his Father which is readily forgiven and reciprocated. And thus Kopa and Kovu are reunited and they all lived happily ever after!!
Here’s a short story to go with the picture (set when Kopa and Kovu are meeting secretly with Simba’s reprimands in between)
Kopa flopped down in the shade of a nearby rock. The evening was chilly but something about being hidden under the overhang comforted him. Kovu followed, a concerned expression pulling at his face as he did so. He laid beside his friend in an attempt to both convey reassurance and also stave off the on-coming cold of night. “What happened?” the darker lion asked quietly. “He lectured me for disobeying him again. He’s so disappointed but I just can’t understand where he’s coming from... He said some pretty awful things about you... and your pride; I’m sick of this,” The Prince sighed, turning his face away. Kovu frowned slightly but his brow soon creased with worry as opposed to anger as he took in his companion’s worn-down and dejected appearance. “As much as it pains me to say so, Kopa, I would expect no less than insults from your Father. He is not a bad lion but he seems rather fond of holding his grudges despite knowing that he is upsetting his Son,” Kovu remarked softly. Kopa nodded faintly before murmuring, “he keeps saying that he's just trying to protect me.” Kovu snorted lightly, “I dunno, Kopa, he seems pretty hell bent on making you miserable.” Kopa exhaled heavily and turned his weary face towards his friend who was illuminated on one side by moonlight, causing his emerald eyes to glitter. ‘Adia’s eyes,’ Kopa thought, ‘not Scar’s.’ He glowered somewhat, “How is it that my Father hates you so much when Scar is not even your Father?” Kovu blinked then tipped his head to look up at the stars. “He was my Father’s, Father and I am his supposed heir,” he murmured after a short pause, blinking again before turning his eyes back towards Kopa, “your Father decided that any relation to Scar was an enemy to him. An opinion which he still stands by, even after all this time.” Kopa’s head dipped and he closed his eyes slowly as he turned his face away, leaving Kovu with a view of his drained profile. “You look exhausted,” Kovu mumbled, moving his head closer to his friend’s. Kopa huffed faintly but the tiny smile that graced his lips for a split second didn’t go unnoticed by the elder of the two. The Prince turned his head to lock tired eyes with Kovu’s, “you’re not looking too great either,” he spoke with a genuine chuckle. Kovu smiled and moved to give Kopa some space again. There was a companionable silence in the minutes that followed until Kopa spoke, his soft voice edged with an underlying note of seriousness, “will you promise me something?” Kovu wondered if Kopa had even spoken at all, the words had been breathed within a quiet sigh – something his usually happy-go-lucky friend was not known for doing. “Anything,” he replied quietly, gazing out over the horizon which was littered with brightly burning stars. “Swear that no matter what happens, we will always stay best friends,” Kopa said with an obvious waver in his hushed voice. “Always,” Kovu murmured after a painfully strained heartbeat, “always.”
Yeah so that’s it really
I worked out that the age gap between Kovu and Kopa is around 3 months (within my theory) with Kovu the eldest and then Kiara is a further 3 months or so younger than Kopa (yes I did look up lion facts to support this theory)
Kovu (c) Disney Kopa (c) ‘6 New Adventures’ Art (c)
Female lions carry cubs for only 3 months so it is possible that Kopa is only 4 months or so older than Kiara. This would only be possible though if the cub (Kopa) was taken from the mother (Nala): if the mother raised the cub till it was old enough to fend for itself she wouldn't have another cub for 2 years. If the cub was taken the mother would come into season within the next four weeks (and thus we get Kiara). Seeing as Kovu isn't related directly to Simba or Nala his age can fall anywhere between the birth of Kopa and Kiara. This of course is only my opinion but I did at least back it up with science haha.