Is Fiona O'Reilly brave in her decision to help the children?

Yes, Mrs. O'Reilly's choice to help the children is one of bravery. Mrs. O'Reilly is of the belief that a woman "ain't got muckle to say about those kind of decisions" (256), yet she makes the choice to secretly house and feed the children and then offers them a wagon and a horse to help them on their journey. This is more than anyone else has offered them. Finally, Polly comments that it is clear that Mrs. O'Reilly "is afraid...I don't think she has ever made her own decision before" (256). These examples prove that, Mrs. O'Reilly is taking great, sacrificial steps to make her own choice and encourage the children on their quest for freedom.