The gay marriage controversy in Britain’s Anglican Church focused recently on a quite practical question: Can gay and lesbian civil partners both register as parents on a baptismal certificate? When Aimi and Victoria Leggett approached the Rev. George Gebauer of Warsash, England, to have their infant baptized, they requested that Gebauer list them both as the child’s mothers. He refused, saying that doing so was illegal and that no child could possibly have two parents of the same sex. Church officials reversed the decision of the retired minister, however. Archdeacon Gavin Collins said “we would be thrilled to carry out this baptism” and to record both parents as mothers....