Raven would probably be the first to sense that something was wrong with Beast Boy. She'd be quiet about it at first, but she'd start keeping a closer eye on him. Maybe she'd make him some herbal tea that she believes has healing properties.
His friends would most likely be very concerned. They would probably bring him things like food and medicine. TK might pray for his quick recovery.
Well, Betty will be super worried. She's always had a soft spot for Archie. She might skip her own activities to stay by his side, constantly checking his temperature and making sure he's comfortable. Jughead, on the other hand, will try to keep things light. He'll tell Archie stories about the latest strange things he's seen in Riverdale to distract him from his illness. Veronica will be more of the practical one. She'll call in doctors or specialists, using her family's influence to ensure Archie gets the best care possible. All in all, his friends will rally around him.
Olaf would try to make Anna laugh. He would tell his silly jokes and do his goofy dances. He would also try to keep Anna warm with his carrot nose. He might even build a small snowman inside the room to keep Anna company when everyone else is busy.
In most 'Naruto gets sick' fanfics, his friends are very concerned. For example, Sakura will immediately start using her medical skills to diagnose and treat him. Sasuke, although he may not show it outwardly as much, will stay by Naruto's side and keep a watchful eye. Shikamaru might come up with plans to make Naruto more comfortable during his illness. And Hinata, she would be really worried and would probably bring Naruto some home - cooked food to help him regain his strength.
Their friends would probably be very shocked at first. For example, Starfire might be a bit confused as she has her own unique view on relationships. Cyborg could be initially taken aback but then might be supportive once he sees that Beast Boy and Robin are happy. Raven, on the other hand, might be more reserved in her reaction, but deep down she might be glad that they've found something special with each other.
Their friends would likely be a mix of shocked and excited. Raven, being the more reserved one, might initially be a bit concerned about how this will change their dynamic as a team. But she would also offer her support in her own quiet way. Cyborg would probably be the most excited, already thinking about building all sorts of baby - related gadgets. Starfire would be overjoyed and would immediately start planning baby showers and knitting baby clothes. Robin would be more practical, thinking about security measures to protect Terra during the pregnancy and the new family once the baby arrives.
His friends would most likely be very worried. They would gather around him, trying to figure out what was wrong. Percy might use his water powers to cool Leo down if he had a fever. Annabeth would be researching in the library, looking for any information on demigod illnesses. Hazel could use her powers to sense if there was any dark magic involved in Leo's sickness.
Sakura would probably be the first to jump into action. As a medical ninja, she would immediately start examining Naruto to figure out what's wrong. She might be worried but also determined to find a cure.
His other friends like Shikamaru would think of the most practical solutions. He might calculate the risks of continuing the mission with a sick Naruto and come up with a plan. Maybe he'd suggest splitting the group, with some staying to take care of Naruto and others proceeding with the mission - related tasks that can't be postponed.
Yamamoto would be more level - headed. He would first try to find out the details of Tsuna's arrest. He might talk to the police or other authorities to see if there's been a misunderstanding. He'd also be a source of support for Tsuna's family during this tough time.