I have to work hard and smart so as to give my family reassurance that I will graduate in time.

reassure |riːəˈʃʊə|verb [ with obj. ]say or do something to remove the doubts and fears of (someone): he understood her feelings and tried to reassure her| [ with obj. and clause ] : Joachim reassured him that he was needed | (as adj.reassuring) : Gina gave her a reassuring smile.DERIVATIVESreassuringly adverb
reassurance |riːəˈʃʊərəns|noun [ mass noun ]the action of removing someone's doubts or fears: children need reassurance and praise.• [ count noun ] a statement that removes someone's doubts or fears: we have been given reassurances that the water is safe to drink.