In the early sessions of my brother's home-brew superhero game using Hero System 5th edition rules,we had our group's first real mission and it was to infiltrate a building that was acting as a front for the Pure, a human purist group who felt that human-alien hybrids were a corruption of the human genome. They had been inspired and started by the world's premiere telepath, Sarah Tabor, who was of the opinion that superpowers attracted too much attention to Earth and set about to eliminate the human-alien hybrids like herself before their presence attracted more attention from the hostile aliens that drove her non-human ancestors to Earth for refuge. Of course, she hid her nature and presented a more zealous and intolerance laced philosophy into the Pure.
Our employer was a PC from a previous campaign and one of the "Founders", Patrick Chen, sort of Reed Richard if Reed Richard had an idea of how to develop infrastructure and make his discoveries and advances useful for the world at large. A deliberate aversion of Reed Richards is useless. He was one of the group of superheroes that had remained non-government and they had a good reputation in the world and a good reputation with most of the official national groups despite being technically illegal. Our teams were called "Seekers" and we were sort of the super-powered black-ops. The ninja to the more public Masks' paladin.
Prior to our mission, we asked Patrick Chen if he had any equipment that would help with getting past security without leaving signs of our presence. My brother decided to make a roll to check if something was available. For those unfamiliar with Hero System, basic tests are rolled with 3d6 and trying to roll less than a particular number. If you're more skilled that number is higher and if you're less skilled, it's lower. In many games, including my brother's, a roll of 3 or 18 are the equivalent of natural 20 or 1 respectively in D&D. On this equipment check, my brother rolled a 3.
This produced a palm-pilot sized device which could be spliced into a security system and would instantly take over the system, digitally edit the registered users out of camera feeds and direct all unedited security footage to the hand device. Since it was so completely designed to "pwn Big Brother" we decided to name it Little Sister.
Most of the first half of the campaign started every mission with our team trying to requisition the Little Sister prototype and complaining if one of the other teams got it first. Then, one day, we had an encounter with Chevyn Banks (pronounced Kevin Banks), the son of the two NPCs from the previous campaigns including Sarah Tabor's daughter. Chevyn and his parents were completely against his grandmother's plans and we encountered him while investigating an unrelated group and being ambushed by the Pure. Afterwards, he decided to take a look at Little Sister and ended up "borrowing" it without asking and bringing it back two days later. After receiving Little Sister back from Chevyn, it started responded to commands with emojis.
See, turns out that while Patrick Chen and his 520 IQ was by far the smartest person in the setting, Chevyn Banks by far had the best understanding of AI theory and decided to convert Little Sister into the world's first true AI. Little Sister then started leaving her hand device and hanging out in the internet with one of the NPC seekers whose power was to enter the internet a la Wireless from Heroes. Her other hobby was locating and exposing child abusers on the net. And now, getting Little Sister on a mission was a matter of negotiating with her.
Eventually, Little Sister worked with Patrick Chen and got a human-seeming android body in the form of an innocent seeming little girl. Sometime after that she generated three children who called themselves, Niece, Nephew, and Lilliputian. All three got their own android bodies. Niece and Nephew went with the creepy twins look while Lilli had a black cat body.
Later on when we were prepping for the alien invasion, Little Sister, Niece, Nephew, and Lilliputian were given ship bodies and used to ferry numerous supers (well, Lilli insisted on being a fighter) to an ambush spot well outside the galaxy which heavily reduced the enemy numbers. Aside from being the ship on the way, they left the ship in human hands to wreak havoc in the enemy ship during the ambush, then jumped back into the ship for the retreat (except Lilli, because fighter...). Our characters weren't involved directly, but as players we got to roll off the results of the attacks and how many heroes died. Note that many of the NPC heroes had been created by us as background figures so we got to watch characters we'd made die and lost to space unable to recover the corpse for resurrection.
Eventually, while Chen-tech was far superior to the aliens, the first fleet did make it to Earth and we entered a protracted battle. During this time, the AIs completely wrecked the aliens because they had nothing to match them. However, the aliens took the habit of destroying the internet infrastructure and the AIs were eventually mostly trapped in their android bodies.
I don't remember what happened to them after we went to the alien homeworld and helped overthrow the dictator, but I think they were fine for the most part. They'd been pulled from the front lines as the balance of what good they could do versus the risk of them getting deleted/killed became more out of ratio for being a good idea.
In any case, after about five months, Little Sister went from a coveted piece of equipment to a quirky friend. And then we got to see her grow and essentially injured and crippled by the aliens as their assaults destroyed the infrastructure she depended on until she was stuck in the body she'd made to interact with humans. I like to think that she and her kids continued to be important Earth residents after the war ended as by that time they'd been pulled from the front lines.