S04E12 Just Say Yes
When Carrie's apartment is going co-op, Aidan proposes they buy it together. She finds a ring in his things, and accidentally insults Miranda who helped pick it out. Trey's MD tries to control Charlotte's reproductive zeal in light of the tough statistics of in vitro fertilization, and Charlotte looks into adopting a girl from China. At the annual Highland Fling, Bunny's objection to a 'Mandarin granddaughter' causes a marital row. Samantha finds out Richard Wright is a tough boss but into quick sexy without commitment, such as on a flight to Rio. Miranda tells Steve he's becoming a father but that she doesn't expect his help.