My Keplerians are externally gender neutral for 5 years. Now genetic testing will reveal gender but they don't do routine genetic testing.
Obviously if a young Keplerian goes to the doctor due to abdominal issues such as abdominal pain, an ultrasound or other form of medical imaging will be used to scan the abdomen and in the process the gender will be revealed(so for example if a CAT scan of the bladder is done to rule out stones, the uterus or prostate will show up thus revealing not only if there are stones in the bladder but also whether the Keplerian is male or female).
But for Keplerians who are healthy, should they get a gender reveal ultrasound at their next checkup or wait until they are 5 years old to see the results of a small spike in hormones? And what besides being rich would factor in to whether a gender reveal ultrasound is done or not?