According to TLC, Duggar, 22, asked Caldwell, 18, to court on Tuesday, choosing a field near the house where he was born as the spot to pop the question. He even gave Kendra a promise ring to represent their commitment to each other.
The announcement was made in a video posted on Wednesday.
"We've been talking for about six months and right when we started talking, we really hit it off really well," Duggar said. "We're both ready for the next step of courtship."
"I'm looking forward to side-hugs and getting to do phone calls and texting and also getting to do ministry stuff out in public and for everyone to know we're courting," Caldwell added.
The two met when Joseph visited the family of his sister Joy-Ann Duggar's fiancé, Austin Forsyth.