Original Age of Majority – Parent’s Guide explains the parent’s role in the age of majority process. It also shares information about guardianship, conservatorship, etc. for families of students with significant disabilities. All children become legal adults at the age of 18 years old, regardless of any disability. If parents want to maintain control over specific areas (financial, health, etc) then they must consult with a lawyer well in advance of the student’s 18th birthday.