Roses grow at last in Freshkill, N.Y. for Mary Catherine Mulligan who arrived there at the age of six in 1941 and is about to leave for Barnard at the close, having weathered poverty, home tragedy and the hallowed confines of old style parish Catholicism. Mary Catherine is the only child of Maureen whose utterances come through as an unpunctuated keen in brogue, and of Rory, a vigorous and likable union organizer. But Rory contracts emphysema and slowly dies as a person before his actual death while Mary Catherine is a scholarship student at the Academy. Humiliated and wounded over the years by hand-me-down clothes and her defeated parents' callousness, Mary Catherine presses for a way out -- the better school, the secret of ""how to act with boys,"" and at least friends ""with a decent vocabulary."" A tale tailored as pristinely as those old parochial school uniforms, but considerably enlivened by some affectionate satiric jabs at the Holy Redeemer ties that really bind. Like Sister's lecture at the blackboard drawing a ""soul"": ""I'm going to make it look like a paper bag."" Or Father Rafferty in the confessional: ""What do you mean you talked back to your mother TEN times!"" In spite of the domestic shadows, an upbeat, sunny tale, perhaps too much so for many, but packed with amusing recognitions for those who remember when dancing cheek-to-cheek was a New Occasion for Sin.