Nyora kupfuurira kweiyi ndima - O'Brien akaberekerwa muJersey City, New Jersey, pana March 7, 1879. Akaenda kuJersey City Public Schools, Academy of St. Aloysius Grammar School uye Saint Peter's College. Akapedza kudzidza paFordham University. Akadzidza mutemo paNew York Law School, akabvumirwa kubhawa ndokutanga kuita basa muJersey City. Akanga ari mutongi wedare rechipiri remhosva, uye akanga ari mutungamiriri wechengetedzo yeruzhinji yeJersey City kubva muna 1917 kusvika muna 1921. Akanga ari nhume kuDemocratic National Convention ya1920
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