it's a pity daeron isn't rhaegel's firstborn son instead of maekar, because if he were? immediately upgraded from failson to favorite nephew status. maekor loves and indulges his brother and has zero expectation of rhaegel as a knight; his son is not different.
rhaegel is meek, and sweet, and unnervingly insightful. rhaegel's conversation is made of riddles and jokes and kind words that cut through maekar's defenses like they're nothing; and also, rhaegel quite solidly helped maekar and baelor take down the blackfyre rebellion via strange portents that made no sense at the time but proved critical in the moment of a skirmish or a battle.
his son takes after him, and that's just fine. maekar is going to apply a number of intimidation tactics on anyone who implies it is not fine for a prince of the blood to be mad and useless. he has been doing this all his life for his brother, his brother's kids get a free pass as well.
he is the rhaegel's son, who speaks strangely himself, and is frightened, always, even worse than his father, by something even worse than whatever it is his father knows.
he is there to look pretty and make alliances and because rhaegel asked maekar to take him son outside the city, in the hopes it might ease his dreaming. he's good company, when he can manage. daeron is obviously not going to enter the lists: he's going to sit besides his uncles and get wine drunk and make unnerving comments himself about the odds of any knight or nobleman. that's what he's for. honestly that's the one thing maekar is looking forward in this tourney.
daeron likes to spend too much time in brothels and taverns? well that's fine enough. at least he's leaving the red keep, rhaegel has been an agarophobe for years. maekar is just glad he's not taking up anything more dangerous. rhaegel went through a phase where he liked to go down to the bowels of the red keep's prison and chat with the criminals there. and then there was the thing with the throwing knives. and the pyrotechnics. daeron's practically functional.
daeron was supposed to go ahead to ashford with his youngest cousin to avoid any unpleaseantness with aerion on the road, only to get lost, appear drunk off his head and muttering about dreams in some inn and no idea where egg is?
maekar is out looking for them. he's worried sick, but he's not very angry with daeron when he finds him. sure, daeron lost aegon, but that's a likely thing to happen. one time when he was five rhaegel lost him when they were out with the kingsguard. not because he was drunk, just because he got one of his fits where he forgot where he was, and when he was, and what he was doing.
sure, young maekar got himself robbed and kidnapped, but he got himself out, slipped off to another ship. ended up in myr for a week having the time of his life watching the fighting pits and working as a weapon's boy before his father's men found him. it was a solid formative experience. it's where he picked up his first mace!
whatever adventure he is on might, baelor comments, do egg some good.
that is easy for baelor to say, though; he is not the one who was put in charge of rhaegel's boy, and he won't be the one to have to answer to rhaegel's ruthless and soft-spoken and too-knowing questions on his conducts and thoughts and ugh, unspoken fear and neurosis.
maekar cannot be angry at daeron. as far as he is concerned, the targaryens are split very evenly into those who fight and those who don't. those who the world will call mad but are only more so the blood of the dragon. that is what maekar is for.
rhaegel's boy looks up at him with his eyes huge and haunted and tells him he has dreamed of a great dragon laid out on the ground at ashford meadows, and a knight who survives it? and he saw the knight at the inn? who is apparently the same nobody aegon snuck off to play squire for?
no more trials or tourneys for ANYONE. everyone PACK UP yes you too aerion. we are quitting this joint YESTERDAY. why? because rhaegel's boy says the vibes are off, that's why.
naturally, aerion has not, for a single instant in his life, been normal about rhaegel's boy.