Fluid in the kidneys? Down syndrome?

Martinezx4 • 24, wife, mother, expecting #2, excited!
Has anyone had a pregnancy or birthed a child where they found fluid in the baby's kidneys during an ultrasound? (I was told This is a soft spot for down syndrome) If so, how was the baby? Did the fluid change? Did baby end up having downs or any other complications? Etc. Any info is great. Thank you (: 💙