Ares was excited.
A new goddess had joined the Olympians and he would get a new sister!
Well, not really sister, as she had another mother. (That ticked him off a little; what could another woman have, that metera¹ didn't have double? After all, she was married to father! Then again, Ares was certain that there was no love between his parents.)
But he decided, that he wouldn't blame his new sister. After all, it wasn't her fault, that she had another mother, right? Right.
Ares wondered, what she was like.
He hadn't met her yet, but metera had said, that today he would!
He already had a few sisters: the Horai (Eunomia, Dike and Eirene) and his little sisters Eileithyia (who was still a toddler) and Hebe (who was still a baby).
They loved him and surely his new sister would love him too.
Metera had said she was a war goddess – just like he was going to be a war god! Maybe they could have some awesome fights and he would impress her with his strength!
Although … mum had said she was already grown up. How was she grown-up? When father had informed them of her impending arrival, he had said, that she was younger than him!
But that would mean … no, he would not finish that thought.
And metera liked her, right? If she liked her, everything would be okay.
The little boy couldn't wait to meet his new sister!
They would play and he would protect her from all the bad guys, he would!
It was already noon. When would he finally meet her? He was getting more restless, then he already was normally.
"Ares, sit still and eat your ambrosia!", Hera scolded her son and Ares tried, he really did! But he was just too excited!
"Metera, when will I meet my new sister?", he wanted to know.
Hera sighed; her son was just always so impatient!
It wasn't that she didn't like Athena (on the contrary, her mother Metis had been Hera's friend, to whom she owed a lot, and Athena was almost her spitting image).
But Ares was too excited for his own good: Athena was completely different from him and Hera knew her son would be disappointed in the end. Her poor little boy.
"You will meet her in the afternoon, okay?", she promised and fondly stroked his black and red hair. The Queen of the Gods loved her son, she really did. But sometimes she was just overwhelmed and couldn't handle his ungovernable temper.
After lunch, Iris came to inform the boy to wait for his new sister in the training hall. Before she could even end her message, he was already off, dashing through the palace.
Finally he came to the gymnasion (why did it have to be the gymnasion? He didn't want to run around naked!²) and waited. But after a while he got bored, so he started doing a few exercises. Sure, he was really good at throwing spears, but practise was important.
He also tried swinging a sword, that actually belonged to his father, but was still too big for him. But the voice in his head (because he had one of those) told him how to do it, so it wasn't actually that difficult.
The pre-teen hadn't noticed, that someone had entered the room, until one of his spears missed its mark and was caught by someone's bare hand.
Ares froze, when he saw the two gods standing in the doorway.
It was a tall woman, the one who had caught his weapon so effortlessly, and …
He paled and began to apologise profusely, because he hadn't meant to hurt anyone and holy shit, he was so frightened of his father!
But instead of yelling at him, Zeus just reprimanded his son: "Ares, how often have I told you, that these weapons are not meant for children! You are way too young to handle those!"
It took all of Ares' courage to not tremble in fear in front of the stranger next to his father.
Calm down, the voice in his head whispered. Think of your role in the play. Play your act.
Right. Play the act.
So he swallowed his fear and got his innocent, huffy child on: "But father, I got bored. And it's not like you ever have time for me or show me how to handle those! Besides, apart from that one spear, I was doing really well!"
Zeus was about to object, but the woman next to him put a hand on his shoulder.
"It's fine, father. No one got hurt after all."
Then she gave Ares his spear back. "Next time, let an adult teach you how to use these, before something like this happens again."
I am an adult!, the voice in Ares' head huffed.
But Ares wasn't listening. "Father, who is that?"
Zeus sighed in frustration: "Well, this is not how I planned this to go down. Ares, meet your new sister, Pallas Athena. Athena, this is your older brother Ares."
She smiled gently: "Hello, brother."
The King of the Gods scratched his head. "Well, I have work to do. You two have fun, I'll be back soon!" Then he was gone.
Meanwhile, Ares stared at the newcomer. This was his new sister?
He stood on his toes and still could only just about reach to the height of her chest.
"Whooooh, you're so tall!", he marvelled, his blood-red eyes growing even larger.

Athena chuckled: "Yes, I am."
"And you look so strange! Your eyes! They are so blue! Like, really blue! Like the sea! And hey, did I already say that you're tall?"
"Yes, b-"
"I want to be tall like that too! No, taller! I want to be taller than you! Then I will be tallest and everyone will stare at how tall I am, because I will be so tall and strong!"
"I'm sure you will be", Athena assured him kindly.
"And when I'm tall and strong, I will protect metera and all my siblings and everyone will like me!"
"Of course, Ares", Athena agreed, even though she wasn't that sure.
But children needed to have dreams and she didn't want to upset her new brother, especially not in their first meeting. Even though she was technically younger, she still wanted to be his big sister, the best in the world. She wanted to be there for him and teach him everything she knew. Well, maybe not everything, but the things he needed to know. She wanted to be his role model, his teacher and just someone worth looking up to.
So she smiled, listened to the 12-year-old's ramblings and agreed, where it was due.
But there were a few things, that irked her.
"Do the others not like you?"
His face darkened. "No. They say I'm insane. What does that even mean?"
Athena bit her lip, but explained: "'Insane' is another word for 'crazy'. But don't worry, I don't think that you're-"
"I'm not crazy!", the boy protested, "I can't help, that I have a voice in my head!"
Her eyes widened.
A voice in his head … ? Now she was concerned.
Because of that, and …
"Can I ask you something?"
Ares looked a little apprehensive, but consented.
Athena suddenly found, that she had trouble expressing, what she wanted to know. But her curiosity was overwhelming, so she tried to put this as tactfully as possible (which was hard, she knew how boys reacted to what she was about to ask).
"Earlier, when you first noticed me and our father, I couldn't help but notice, that you were rather … uncomfortable."
Afraid. A word no boy or man liked to hear about himself. But it was so obvious, that he had been positively frightened – of Zeus.
Why was he so afraid of his own father?! That was not normal!
Unfortunately, Ares seemed to get exactly what she meant.
He gritted his teeth. Shit.
"You mean 'scared', don't you? I wasn't scared! Boys and men don't get scared! That's pathetic!"
Athena frowned. "Not really. Sometimes it is, but more than often it isn't."

That took Ares by surprise. "What? I don't get it."
She sighed: "How about we sit down and I explain it to you?"
This really weirded him out (and agitated him, he was not gonna lie), but he humoured her.

The blue-eyed goddess and he sat down and she began to explain.
Unfortunately, she noticed after a while, that the boy had stopped listening after a while and now was drifting off.
"Ares!", Athena said sharply and he startled awake.
"Sorry, sorry!", he apologised hastily, "But I didn't understand a word and-"
"Calm down, I'm not angry", she tried to soothe him, "But next time let me know, if you can't keep up. It's kind of hurtful, when you're trying to explain something and the other just dozes off."
He looked really down.
Fantastic. This was not how she had imagined this to go down.
After some awkward silence, he spoke up again: "Your question from earlier …"
"You don't have to answer it, if you don't want to", she said.
He sighed in relief: "Good. Because I don't."
"But if you ever feel ready … if you want to talk to someone, I'm here for you, okay?"
Ares tilted his head. "You're weird."
Athena smiled lopsidedly. "So are you, brother."

1) Metera - Greek for "mother" (I hope this is right, because I don't speak Greek)
2) Gymnasion actually means "place of the naked" (gymnos = naked), because students (male only) usually wore little to no clothing, while performing their gymnastics and other sportive exercises.