Thomas Rhett and Wife Lauren Expecting a Baby – and Adopting a Child from Africa

In December, Thomas Rhett and his wife Lauren were on a week-long safari in Tanzania — a rare break from touring for the singer — when Lauren started feeling sick.

When the country star offhandedly suggested his wife take a pregnancy test, Lauren scoffed. “I was 100 percent sure I was not pregnant,” she tells PEOPLE exclusively.

Months earlier, the couple had quietly started the process of adopting a baby from Africa — and stopped trying to have a baby on their own, she says.

“When we began the adoption process, we said, ‘Let’s wait, let’s give this adopted child his or her time with us and then we’ll continue our family,’ ” Lauren explains. “So I was convinced it was food poisoning.”

We’re so happy to announce that we are pregnant & in the process of adopting a child from Africa! Safe to say life is about to get crazy!

— Thomas Rhett (@ThomasRhett) February 15, 2017

But just in case, she decided to check. Certain the result would be negative, Thomas Rhett left his wife with their friends, Florida Georgia Line’s Tyler Hubbard and wife Hayley, who were on safari with them, for a treadmill workout when Lauren took the test.

Sure enough, it was positive. “I’m jumping up and down, Tyler’s giving me a bear hug and Hayley’s running out of their room and I’m like, ‘Thomas Rhett is not even here!’ ”

The trio ran to the gym and blurted out the news.

“I was in complete and utter shock!” says Thomas Rhett, 26. “No one is ever prepared for something like that. It is almost like we suddenly had twins.”

It was, the couple says, the sweetest surprise they…