For four years, Kerstin fought hard against infertility and endometriosis. The process was exhausting and frustrating at times, but she persevered. As you can imagine, Kerstin and her husband were over-the-moon when they unexpectedly discovered they were pregnant during the week of July 4, 2016.

A few weeks later, their initial ultrasound revealed the sex of their baby. Kerstin’s beloved father, Robert Paul, was on-hand for the ultrasound. He even learned the sex of the baby before they did.

The gender reveal party, when everyone would finally learn the baby’s sex was in September. Kerstin and her husband had two names picked out and ready to go – one for a boy and one for a girl.

The couple’s plan was to learn the baby’s gender, and then depending on if it was a boy or girl they would bring out a cake with their baby’s chosen name placed on the icing so their family could see the gender.

Grandpa Robert may have known the sex of the baby all along… but little did he know that if it was a boy, Kerstin and her husband had a huge surprise in store for him.

Check out the video!