Chi-Chi realized over time that Golina was not hers to baby as she did Gohan. The girl belonged primarily to Goku, but Goku belonged fully to Chi-Chi. Luckily, Lina was much too strong-minded to be ordered and much to smart to be persuaded into joining Gohan in his studies. She was already several levels higher than her brother intellectually, therefor, she became the tutor.
Though first Goku insisted on seeing exactly where his daughter was in her training. The duo used the yard as a battleground.
"I don't know, Da. Mom will be mad as you if we mess up the yard."
"You're right," He flew several dozen feet into the air, powering up into Super-Sayain as he did. He was followed by Lina, who did not power-up.
"What's wrong?" Goku asked.
"I've never unleased my power on earth. I'm kind of nervous."
"Don't be. The planet is resilient; let 'er rip." Lina shrugged and let out a bone-chilling scream. The power she had wore as a slight aura before exploded outward. The winds stripped the trees of there bark and a blinding light flashed, leaving Goku's sight spotted. When he could see clearly, Goku relieved that she was finished. The wind had lessened to a formidable gust and the light that had flooded the air was now in her eyes. The girl's now blonde hair fanned out around her as sparks of lighting danced though it, like a flashing neon sign advertising blood. He gulped, but refused to back down. He shot at her like a bullet out of a barrel, she swept gracefully aside. He came at her again with a barrage of heavy blows, moving as fluid as water, though water with a target that kept moving.
By now Gohan had come out to watch. He stared into the air, slack-jawed as Lina literally flew circles around his father. In a second they were off. Lina quickly shot ahead of the man, moving faster than even Gohans' eyes could see. Goku soon gave up the attempt to keep up and simply floated in midair, doing something close to pouting. For a moment there was no sign of the girl. Then a great sonic boom left every pane of glass in a mile radius shattered. She had broken the sound barrier and was still going. That is until Chi-Chi scrambled out of the house, her hand pressed to her ears and screaming at the top of her lungs for Goku to stop all this nonsense this instant!
Lina slowed and reappeared behind her mother. "I'm sorry, I didn't mean to."
"Oh, this is all your father's fault dear, now be a good girl and pick up the glass in the house for me."
Lina entered the house with Gohan who picked up a broom and started sweeping the incredibly small amount of glass. "I thought there was more glass in the house than this."
"There is," Gohan replied, opening a cupboard to show plates, cups, glasses, and bowls, all intact, "but Mom has had this place Dad-proof for a long time," He showed his sister the thick side of the door, "See? It's insulated."
She grinned and motioned for Gohan to step aside. He did and with one wave of her hand and outburst of her power all the glass shards swept themselves into the trash bin.
"Keri?" Gohan asked inquisitively.
"Jalnin," Lina corrected. At that moment the twins' parents walked in. Goku looked forlorn and violated; Chi-Chi resembled an erupting volcano. Gohan poked Lina in the side, whispering. "Lets go learn about that Pyfagoren Theory thing?"
"Pythagorean Theorem, Gohan," Then seeing the look on her mother's face soften at her son's willingness to learn, added, "Lets go."
The two were in the middle of the lesson when company arrived:
"Okay, look here," Lina coaxed Gohan to understand, "The legs of the triangle can be labeled 'a' and 'b'. The hypotenuse is labeled 'c'. Now, if the legs are seven and 8 inches, how long is the hypotenuse?"
"113?" Gohan practically guessed.
"No; you forgot to hit the radical button"-
Yelling sounded through the house in a voice that was known to one, but not the other, "GOHAN!? GOKU, GOHAN!?". Lina walked out into the hall and was immediately the target of an onslaught of violent questions.
"Where is Gohan!? What have you done with them!?"shouted the boy with long lavender hair. He had finely carved features: a firm jaw; a proud, strait nose; and his mouth was sensual, grim and set. His power floated in the air like a threat and his entire body was laden with muscles.
"I didn't do anything to them," She shouted back, defensively.
"Where is Gohan?" The man asked slightly relieved. At that moment Gohan entered the room. "Gohan?"
"Hi, Trunks. Oh, this is my sister: Golina."
"H-Hi. I'm sorry. I felt a huge amount of power from here; What was it?"
"Her," he nodded his head towards the girl.
"Her? But she doesn't have any power; she's a girl!"
"Oh, yeah? Touch her." The youth did and Lina's power flooded into him, making him jerk away as if she had struck him. He stared, mouth agape, at this girl. *This isn't possible! She is a girl!!! Girls cannot be Sayain!! They just can't.... No, wait. This is my father talking, not me. Look at her, you dumb-ass! She's gorgeous! She is gorgeous and Sayain. I have got to stop arguing with myself! * The near-man told himself as he took in her appearance until Gohan had enough. "Trunks!!" He raised Trunks's head and eye level several inches, "She's up there!"
Trunks Blushed a deep crimson and pushed Gohan away. "I know that!"
Lina watched the two exchange venomous glances and grabbed Gohan by the arm, dragged him back into the room and sat him down in the chair. "Hit the radical button!"
"Give it up! I only asked to come up here to avoid a global meltdown from Mom! Everything is blown over now so why can't I go over to Trunks's house?"
He hit the radical button tossed to calculator of Lina and dashed out the door with Trunks. She rushed after them.