I work in a special needs preschool class. It's surprising how many parents send their kids to school sick and then claim they "didn't know he was sick!" (do they look at their kids in the morning?) Or that they "didn't know the policy" when we've sent it home to every family at least 3 times this year.
Basically, if a child has a fever, he should stay home. He can't return until he is fever-free for at least 24 hours. If his temp was up the night before but normal in the morning, he should still stay home (it hasn't been 24 hours yet).
If the child is coughing a lot, he should stay home. A little residual cough after a cold is to be expected. But, constant coughing to the point of gagging is a reason to stay home. Last week we had a child gag from coughing and threw up on the bus. The bus driver turned around and took him home and the mom couldn't understand why! She told the driver there were extra clothes in his backpack. This kid is in a special ed preschool class in a public school. The school rules for sick kids apply to him too. The mom called us and expressed her surprise that the driver brought him home and was put out that she would have to miss work! All because the driver wouldn't deliver us a kid covered in puke! That same day, another little girl coughed so hard that she threw up in front of her circle-time chair. Luckily, it was dismissal time and grandma was just outside the door.
If the child's nose is running green or yellow, he should stay home. We don't mind wiping the occasional runny nose if it's running clear. But green or yellow indicate an infection (usually viral but still contagious). The kid needs a couple of days at home to feel better and ensure no one else will be infected. The other problem is that these kids haven't developed their self-help skills yet. They wipe with sleeves, on toys or not at all and spread it around.
If a child has thrown up or had a bout of diarehhea less than 24 hours ago, he should stay home. If the last episode was 24 or more hours ago and he has no other symptoms, he can come to school.
If he's been diagnosed with pink eye, he should be receiving the medication and the eye should be free of discharge. We had a kid with pink eye last week. After 2 doses of meds, his mom said his eye was still crusty. We asked her to keep him home another day until the eye was clear. Pink is OK but oozing and crusty can still be contagious.
If a kid has a rash, he should stay home until it's diagnosed and treated. We had an autistic boy rubbing his back on the carpet one day. He's non-verbal and couldn't tell us what the problem was. When we checked under his shirt, he was covered with red dots. His mom said she noticed it in the morning but thought his skin was just irritated from her new laundry soap. Turned out he'd developed a food allergy that needed to be treated. So, don't send rashy or otherwise itchy kids to school or daycare! Do you know what it's like trying to deal with an autistic kid who's so uncomfortable? They get really cranky! (That's probably why his mom sent him to us - she has a history of similar situations.) That same day, she said she would "try to come and get him early but the baby was sleeping so she couldn't come right away." What's wrong with putting the baby in his car seat and letting him sleep in the car? If his nap is cut short and mom doesn't get her "alone time" for the day, tough! She's a parent and her older kid is sick at school. She needs to put on her big girl panties and deal with the fact that her day might just be interrupted without prior notice! (I could go on and on about this mom, but that wouldn't be polite!)
If kids have open sores that can't be covered by bandaids, they should stay home. We had a kid with cold sores under his nose that were oozing. We called grandma and asked her to pick him up. Turned out he had Impetigo - a skin infection that often occurs on the face during a cold. All the nose wiping can cause the skin to break and be subject to infection. Little kids carry all kind of stuff under their fingernails.
I hope I haven't forgotten anything. As you might be able to tell, sick kids at school and daycare if a real hot button for me. I get so irritated when I see a miserable, droopy kid get off the bus. You can also tell something's up when a mom or dad shoves the kid through the door and makes a quick exit. By the time we notice something's wrong with the kid, the parent is long gone. I can't count the number of times we've set up the sleeping bag in the corner for a sick kid to rest while mom was "on her way" to get him. These kids certainly can't learn anything when they're sick. Some don't have any language to express themselves so they just cry. That really disrupts the class because the other kids are so distractable. They're all watching the one who's upset and can't do their work. Some of our kids are anxious and can't stand seeing another kid so upset. So they get upset, too. Then the teachers get anxious. Then the classroom is basically frozen until the sick one goes home.
To the OP, I would try to be firm with your nephew. Just because you're family doesn't mean you shouldn't get some consideration. The fact that you have two little kids of your own and a husband who seems to catch every bug that comes along should be a clue to the parents that they shouldn't bring a sick child to your house. Good luck!
