Near the end of the second of these novels their young heroine, Maura, laments: “Jesus, Mary and Joseph . . . are we Irish to get no peace in this world?” Her question might well serve as epigraph for the tale of trials and tribulations which befall her and her brother Patrick when, fleeing from the Great Famine of the 1840s, they emigrate to America. These travels demonstrate more than adequately the truth of the notion that when sorrows come they come in battalions.

The overall picture that emerges from these near-700 pages is bleak and harrowing. Whatever the determination of some historians to refashion our perceptions of the Famine, its significance in Irish folk memory remains central. It is a story which requires and deserves any number of re-tellings.

The long trail which takes Maura and Patrick from their tiny native village of Kilonny to Boston provides Avi with the opportunity to create a rambling, picaresque pair of novels which - for most of the time - sustain the reader’s interest. They are based primarily on a view of story which sees it as a series of flights and encounters, of unexpected (and not always totally credible) discoveries and of dramatic fluctuations of mood. If the whole is sometimes threatened by a note of breathlessness, it is invariably redeemed by the introduction of yet another Dickensian grotesque, bringing the possibility of comfort or chaos to younger lives.

The breathlessness is, in the main, a consequence of the choice of structure. In essence, it is based on the quest, deriving from the fact that Maura and Patrick’s prime aim in travelling to America is to be reunited with their father who has emigrated earlier. Interwoven with these is the quest of one further, and superficially very different, child to find a haven from domestic maltreatment: this, by one of the coincidences which pepper the narrative, is the aristocratic Laurence Kirkle, son of one of the landowners largely responsible for Ireland’s misfortunes.

The three children’s shared journey is tracked in a long succession of short chapters, the content of each of which is signalled in a “now read on” signpost title. There is enough (perhaps more than enough) here to keep the pages turning: the romantic, the realistic and the sentimental combine to remind us that brutality and persecution can take many forms and that - at least in children’s historical fiction - they will ultimately be routed by youthful perseverance and resilience.