Yes. Why not? If he’s old enough to kill in cold blood, he’s old enough to die for his crime. They charged him as an adult, and he knew what he was doing. He hasn’t been declared insane, so why is there an ethical objection to this?
Maybe grandma was an nasty old bat that beat him with his cane...
His parents maybe don't want him because they are low life scum sucking dogs that don't give a damn about anything but themselves...
The kid may just be mentally insane and in a civilized country these people are institutionalized ...not executed for their crimes since the definition of insanity is you do not know the difference between right and wrong...
Should he ever breath the free air again...No
If he is judged to be mentally fit...lock his ass up forever...