They walked in the compound, laughing and playing. The four of them instinctively went into the common room. Unaware of what they were going to find. Their faces changed the second they realized. The twins stopped laughing at the confused sight of their parents. Loki was there.

Loki: "Hello there captain. Miss Romanoff."

Steve: "Loki ?"

Nat: "What are you doing here ?"

Loki: "Are those children ?"

Steve: "Don't even think about getting closer to them."

He opened his arms pulling his children behind him. They knew what that meant. They hid behind their dad Without asking questions, even if they didn't really understand what was going on.

Loki: "Well, as you can see captain, I am chained to the wall so..."

Steve relaxed his arms and the twins slowly came out of behind him. Thor walked into the room.

Thor: "Hi, you've returned."

Nat: "Where is everyone ?"

Thor: "With Tony in the conference room. I am just keeping an eye on my brother."

Steve: "Can you stay with the kids as well ? I think we should go to the conference room."

Thor: "Of course. They are waiting for you two."

Nat and Steve left. The twins got closer to Thor and sat on the sofa.

Charlie: "So, you're Thor's brother."

Loki: "I am Loki. Son of Odin. God of mischief."

Lexi: "You don't look like brothers."

Thor: "He is adopted."

Charlie: "Why is he chained to a wall ?"

Thor: "He did some bad things."

Loki: "Excuse me brother, but there is something that I don't understand."

Thor: "What's the problem Loki ?"

Loki: "Why are there children here ?"

Thor: "May I present you the twins, Charlie and Lexi."

Loki: "That does not answer my question."

Thor: "They're Nat and Steve's children."

Loki: "Wait what ?"

Twins: "What are you gonna do with him ?"

Loki: "Since when are Captain America and Black Widow together ?"

Twins: "Really long time."

Loki: "Since when are they parents ?"

Twins: "Well, we're 10 so... Ten years."

Meanwhile, in the conference room Tony is announcing that they might have to leave sooner for that mission. Even though it was hard for them, Steve and Nat knew it was the right thing to do. They had to fight, to protect the world they were leaving in. Sometimes they thought about giving up, leaving the job, but then they remembered that they were fighting to keep the world safe, a world where their children lived. They couldn't let anything threaten their kids' lives. So, as hard as it was to accept that they wouldn't see them for a few days, they had to do it. There was still something that released their stress. Wanda and Vision were staying in the compound and would babysit the twins.

They walked back into the common room. Thor, Loki and the kids were still there.

Loki: "Ooh, the Avengers are back."

Thor: "Shut up brother."

Loki: "Cap, Natasha, I believe I'm late for the congratulations."

Steve: "You told him about the engagement ?"

Loki: "What ? No, I was talking about the children. You're getting married !? How did I not know about that ? Am I not invited ?"

Nat: "No you're not."

Tony: "Why is he still here ?"

Thor: "Well I was gonna take him to Asgard but I have been requested to babysit."

Steve: "You're free to go now Thor."

Thor left with Loki to put him in prison in Asgard. While Nat and Steve had to explain to the kids that they were leaving on a mission and that they had to stay in the compound with Wanda and Vision. They explained that they were leaving for a couple of days and told them to be nice and to listen to Wanda and Vision. Then, they took the Quinjet with Tony, Bruce, Bucky and the others.

The twins got up to their room with Wanda following them. They started looking around, trying to find something to play with. A little later Vision came in.

Vision: "Hello, can I join you ?"

Charlie: "Of course we're playing Uno."

Vision: "Thank you."

Wanda: "Actually, can you bring some water while we finish this and then you can join us for the next one ?"

Vision: "I'll be right back."

While Vision wasn't there Wanda kept a close eye to something that had felt weird for her. Then he came back with some water bottles and sat down on the ground, in between the two children.

Wanda: "Guys, what color are your eyes ?"

Lexi: "Light blue, almost grey, why ?"

Wanda: "Just because now they are pretty much yellow."

Vision: "Indeed, they are."

Wanda: "But they weren't a minute ago."

That seemed weird for all of them but as it was only an eye color they didn't give it much importance and they kept playing until Vision walked out of the room to order some pizza for dinner as his cooking skills were not that great. At that moment Wanda noticed that once again the twins' eyes color changed to their usual. It was only when vision came back in and that the twins' eyes color changed again that she realized it.

Wanda: "Vis, you mind stepping back a little."

Vision: "Sure not, why ?"

Wanda: "You are making their eyes change."

Vision: "How is that possible?"

Wanda: "I don't know. But look, their eyes are grey now, step forward... And they changed to yellow."

Vision: "That doesn't make any sense."

Wanda: "It doesn't look dangerous so we'll just wait until Steve and Nat come back to tell them."

In order to keep them safe and keep themselves safe they thought it was best if Vision kept his distance with the twins. But as Wanda and him were the only ones left to babysit, he sometimes had to interfere with them. And everytime he did, their eyes changed colors.

During the five days that the mission took them, they didn't find out why the twins' eyes changed colors near Vision. It was only about fifteen minutes before their parents came back that they figured it out.

Wanda needed to take a shower so Vision was in charge of the twins. They were playing hide and seek. Vision was hidden under one of the beds and Charlie under the other one. Lexi walked very close to them both, in the tiny gap between both beds. Without noticing she passed through the wall.

Wanda: "Hey guys I just received a call from Tony, they're on their way back here."

Charlie: "YES ! I miss mom and dad."

Vision: "Wanda you are not going to believe this ! Lexi passed through the wall."

Wanda: "Guess we just discovered a new power."

Lexi: "Not really I tried to get back in but it didn't work."

Wanda: "What color were your eyes ?"

Lexi: "I don't know."

Vision: "Now that you mention it, Charlie's eyes were yellow."

Wanda: "You know what else is yellow and has some sort of power ? The stone on top of your head."

Indeed, the twins could use the power of the infinity stones when the two of them were close to one or all of the stones, but they had only found out about one.