The OP has asked for book recommendations that can help explain the Catholic stance on evolution to her brother so that he can intellectually find his way back to Rome. If you have a book recommendation, post it.
For the OP, recommendations of books by Catholics about evolution.
StAnastasia
Deane-Drummond, Celia.
Biology and Theology Today. London: SCM Press, 2001.
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Brave New World: Theology, Ethics and the Human Genome. Edinburgh: T & T Clark, 2003.
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Creaturely Theology: God, Humans, and Other Animals. SCM Press, 2009.
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Wonder and Wisdom: Conversations in Science, Spirituality, and Theology. Templeton Press, 2006.
Delio, Ilia.
Christ in Evolution. New York: Maryknoll/Orbis, 2008.
Edwards, Denis.
Breath of Life: A Theology of the Creator Spirit. N.Y.: Maryknoll/Orbis Books, 2004.
Haught, John F.
Deeper than Darwin: The Prospect for Religion in the Age of Evolution. Boulder, Colorado: Westview Press, 2003.
Haught, John F.
God after Darwin: A Theology of Evolution. Westview Press, 2000.
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Purpose, Evolution and the Meaning of Life. Pandora Press, 2004
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Responses to 101 Questions on God and Evolution, Paulist Press, 2001.
Hess, Peter M. J., and Paul L. Allen,
Catholicism and Science: a Greenwood Guide. Westport, CT: Greenwood Press, 2008.
Hewlett, Martinez, and Ted Peters.
Can you believe in God and evolution? A Guide for the Perplexed. Nashville, TN: Abingdon Press, 2006.
McMullin, Ernan, ed.
Evolution and Creation. University of Notre Dame Press, 1985.
Miller, Kenneth R. Finding Darwin’s God: A Scientist’s Search for Common Ground between God and Evolution. New York, NY: HarperCollins, 1999.
Peters, Ted, and Martinez Hewlett,
Evolution from Creation to New Creation. Nashville: Abingdon, 2003.
Russell, Robert John, William Stoeger, S.J., and Francisco Ayala, eds.
Evolution and Molecular Biology: Scientific Perspectives on Divine Action. Vatican City State and Berkeley: Vatican Observatory and CTNS, 1998.
Welker, Michael, and John Polkinghorne, eds.
The end of the world and the ends of God: science and theology on eschatology. Harrisburg, PA: Trinity Press International, 2000.
Józef Życiński, Józef, Archbishop.
God and Evolution: Fundamental Questions of Christian Evolutionism. Washington, D.C.: The Catholic University of America Press, 2006.