What is the expiation for someone who caused an accident that led to the death of one person and partial paralysis of another, knowing that he was not fasting and was young at the time?

If an act of killing is committed by a person who has not reached the age of fifteen lunar years, and no other signs of puberty have appeared on him, then only blood money (Diyya) is obligatory, and it falls upon his 'Aqila (male agnatic relatives), due to the Prophet, peace and blessings be upon him, saying: "The pen has been lifted from three: from the child until he reaches puberty, from the insane person until he regains his sanity, and from the sleeper until he awakens."