He does have parents.
Currently an only child, I think.
Many are born just fine. Yishai wasn't.
His parents are, at the very least, decently well-off. Yishai wouldn't call his house particularly wealthy, as many in his social class are well-off to begin with, and few that high up the societal ladder struggle, but they are well-loved. Yishai is, as well, an only child, and his parents' attentions aren't split between multiple children. Unlike other children, though, Yishai couldn't run and play quite as well. Even as he tried, rather quickly, he'd tire out, find it difficult to breathe, difficult to stand, and eventually, collapse outright. Despite the best medicine had to offer in their vicinity being available to him, it only got worse, as he got older, until, some days, he can't stand at all.
Yishai never did let it get him down. What he lacked in physical capability, he made up for with mental ones, and a temperament that was, to many, rather magnetic. He is, perhaps, a ray of sunshine on a grey, cloudy day. He learned to teach others to do the things he couldn't. Perhaps he couldn't physically repair the structural integrity of a failing tower of blocks, but he could show others how to. Yishai may not have been able to physically sail across the open seas, but he learned to teach others how to do it. And, eventually, he may not have been able to reach out and hit the right points on another person as to make their nervous system momentarily freeze up, but he could teach someone else to.
Most figured, the boy, if he lived long enough, would eventually become either a healer, as he had the temperament for it, or a teacher. Somewhere amid researching what in the world was wrong with him, though, he decided he rather enjoyed research in general. As is, perhaps, often an eventual outcome in situations such as his, Yishai eventually yearned to see the world he read about, to go beyond Dalmasca, and see the rest of Azaleon for himself.
It is often believed, now, his own will to live and learn to manage his own frailty, led to him overcoming it, to some extent. He hit an all-time low, for him, died for roughly three minutes, and then came back, somehow. Over time, he grew stronger. His weakness episodes came less often, he coughed incessantly less and less, his breathing became stronger and more deliberate. When he did have his fits, he started trying to learn to curb their severity, and discovered, if he worked with it, instead of fighting it, his control over it and ability to abate his fits became easier.
Even now, however, he still cannot do many of the things others can. At times, his ability to even walk is impacted, as he becomes winded faster than most. At the worst, he's stuck in bed for a few days to a week with a fever, until it goes. Still, no one is entirely sure what is wrong with him, exactly, but he's never come anywhere close to the low he'd hit when he died. Some mastery of dance and breathing control angled him more capable of handling it, when his body seems determined to fail on him too soon, but he still has these episodes of weakness. Because of this, Yishai is very particular about whom it is that he trusts, and who he spends extended periods of time around.
In the interim, he's taken to seeing everything there is to see in Nydema, and hopes, someday, to be able to go beyond the borders of his home nation. He lives each day as if it were his last, has thrown himself into scholarly pursuits, and his parents decided he needed a guard. Haaaa. Maybe his guard needs a guard from his incessant rambling.
His vague disease/condition thing operates basically like a combination of tuberculosis and muscular atrophy. Not contagious, though.
He is a mage, and he is a water affinity, but most don't really know that because sorcery really wears him down fast, and he won't use it unless he absolutely needs to.
Makes a decent healer, though.
Shai's ears are pierced. Usually has small studs in them. I mean very small.