It happens a lot. Before I got married I was nanny, they interviewed me while pregnant with their first baby. They had been told by the first ultrasound tech that she was as sure as sure could be that baby is a girl, had another scan a few weeks later and told the same again by a different ultrasound tech. Once I had been given the job they showed me around the house/nursery and had the most beautiful pink nursery, with Erin Catherine painted on the wall, the nursery furniture was white with pink roses painted on, the whole room was basically paradise for a little girl. Four weeks later Samuel arrived.