When Kili and Lili turned five they started doing meditation with Fili for real now, and no more running around was allowed during that time. They got used to it in time but it wasn't as fun. However it did help them focus. Balin started using some elvish words with all 3 of them around this time so they could get used to it.
When Kili and Lili were six, Kili finally got to climb up a tree really high when Fili wasn't around to watch after them, as he was helping Thorin with some little things in the forge, Kili went up close to 40 feet, while Lili stopped at 20 feet because she knew they weren't supposed to go higher. While Kili was reaching to go higher the branch he was standing on broke and he fell, if he hadn't hit a few branches on the way down he could have possibly died, however he thankfully only broke one of his arms and got a 4 inch scar on his right leg. Fili was mad that they didn't stop but was also scared out of his mind and worried about his brother. Dis sent a letter by raven to Elladan, informing him of what happened and partly blaming Kili's elvish blood for wanting to climb trees. Elladan wrote back about a similar situation when he was younger and told her it was a young boy thing, not necessarily an elvish thing. He wrote he was happy that Kili was mostly okay though.
When Kili and Lili were eight they started to learn carving as a craft.
When Kili and Lili were ten they started helping in the forge with little projects.
When Kili and Lili were eleven they were taught all sort of flower uses, under the guise of how it could be used for medical purposes by Balin, however it was one of the conditions that Elladan wanted for his kids.
When Kili and Lili were thirteen they started weapons training, at first Thorin and Dwalin wanted it to just be Kili, however they knew that Kili and Lili stuck together and stuck with Fili as much as they could. They would never be able to keep Kili from teaching Lili and they wanted to make sure they were all safe. So while Fili preferred to use a sword, Kili preferred to use staffs or bows, he did learn everything else but he had a preference that was very noticeable. Lili was able to train with everything, although the bigger axes were hard to wield. She preferred a shorter sword. To compensate for longer range opponents she made sure to have throwing axes and knifes that she used frequently. She'd gotten to the point to where she could hit the center of targets better than Fili could. All three of them together still couldn't beat Dwalin but they had hope that in time and with practice they'd get better.
When Lili was 14 she was told that she would have to start learning dwarvish cooking and other household chores that usually the dwarrowdams took care of, at first she threw a fit because she wanted to always be with her brothers. Instead she ended up being able to talk her mom and her uncle into getting the boys to join as well. Afterall they could stand to learn adequate cooking for when they went traveling, they could learn stitching for their travels, cleaning and so on. It ended up turning out quite well and their home had been near spotless since.
When Kili and Lili were 15, when Fili was 20, they were taught quite a bit of elvish by Balin, he had been taught by Lindir. They practiced daily and were taught the importance of it for diplomatic purposes. They grumbled naturally, because even with the elves helping them, most dwarves still were not very large fans of the elves. Balin tried to make it as fun as possible so it wasn't completely boring, but it still took Kili months to learn and remember most things. By the time the elves came that year in the fall though, all three of them could speak fluent conversations with the elves that came. Elladan and Elrohir were quite pleased and very happy with what was happening. Elladan was still sad over his past but was so happy with his children.
From 15 to 30 Kili, Lili, and Fili attempted to be together as much as possible, and they still practiced the things they learned together. However their training was also going into individual directions as well. Fili was taught leadership that he had to know being the heir to the Thorin, Kili was taught some of this as well but not nearly to the extent that Fili was. Kili was taught a lot of accounting, and some diplomatic things but mostly he learned by sitting in with Thorin on some meetings. In the future he was to help Fili with running things, whether they were still in Ered Luin or if they were able to take back Erebor. Lili was taught diplomatic negotiations by Balin, as she would be the main contact with others, she had the calmest temperment of the three. She spent a lot of time with Ori as he was being trained as a scribe by Balin as well.
From 30 to 60, the three still tried to spend as much time as they could together. They went hunting and camping, they helped guard traveling caravans. They went to different towns to negotiate trade deals. All of this was usually with a few adults, but the important thing was that they were together. They knew that they would never leave each other, they were meant to be very close siblings and best friends forever.
During all of this time they still received letters from their father, their uncle and grandfather. They weren't entirely sure why they weren't allowed to meet them yet but they did know that amad wasn't all that happy when it was brought up, so they tried not to that often. They learned quite a bit about the other side of their family, and told them of different adventures and little bits of mischief that they would do. They seemed to get on well through letter. They couldn't wait to meet him one day...
Between 60 and 70, they started talking more of relationships, they would become of age when they turned 70. Mostly Fili and Kili teased Lili about different dwarves who likely had an eye on her, however if anyone ever made a pass at her, they were very defensive of her. Lili for her part tried to give as good as she got right back at them, however to be honest there weren't enough eligable dwarrowdams around for her say a lot. She however did have a crush on a certain dwarrow. Because of how much time she spent with Ori with him being a scribe and her being a diplomat in training with Balin, she saw Ori's family often. She had become quite engrossed with anything concerning Nori. There was something about him that she just loved. When she turned 70, she actually attempted to let her feelings be known. She got the courage up and did something slightly scandalous, she went up to him when they were alone and kissed him lightly on the lips. He blushed furiously, backed away, got all fidgety and left the room. He came back within a minute, there was a lot of hesitation in his voice, like he was searching for the right words to say. He was finally able to get out that he was sorry, he did't feel for her like that and that he was with another. He tried to be as gentle as possible about it, he felt bad but he couldn't see her. Lili understandably was crushed, but she never said a word of it to her family. She thought it was private and she also felt a little bit like she wasn't good enough, but mostly she was just sad. However soon she got back to her normal self and was able to enjoy time with her family again without them really noticing a thing.
Seven years later her world fell apart, not because of some dwarrow, but because her uncle and her brothers left her to go on a quest to reclaim Erebor. She had pleaded until she was blue in the face to go with them, however all of them insisted that she shouldn't go. Dwarves protect their dams, they don't put them in needless danger! She brought up that she was taught the same as Fili and Kili on weapons and that she could be an asset. They still said no, that if they should die that she could carry on the Durin line. She was devastated the day they left, they went one way and she... she didn't go home. She was mad, hurt, and feeling betrayed, her brothers who said they would always be by her side had left her, so instead she went north several miles and went camping. She was at least kind enough to leave a note on the kitchen table for her mother, so that she would worry less.