The ninth-season The Bachelorette star revealed in April she's pregnant with the couple's first child, and now, she and Siegfried have shared the news they are expecting a son.
"We are so excited to share that we will be having a little baby BOY! Our hearts are so full of love for our little man already and we can't thank you all enough for the extra love you've shared during this special time!" Hartsock, 30, captioned an Instagram photo of the couple with their Golden Retriever puppy.
In the picture, Siegfried, a former professional baseball player, is holding a baseball with the words, "It's A Boy," written on it.
One day before making the big announcement, Hartsock posted a photo on Instagram of the pair cradling her baby bump.
"The best part about this new chapter in life is going through it all with the quirkiest, most thoughtful, and lovable man I know. We can't wait to be parents to the precious lil soul growing inside me," Hartsock captioned the image.
Siegfried, 30, toldUs Weekly that he and his wife "couldn't wait" to find out whether they were expecting a boy or girl after walking out of their ultrasound appointment. They found relief in the results.
"It makes it all more real and, like, this is really happening!" Hartsock added. "We have a name picked out! We're keeping it in our back pocket right now, but that'll be a surprise to everyone!"
While Siegfried can't way to play baseball with his little boy, he told Us, "But whatever happens, we are not going to be one of those parents that says, 'You have to do this.' He can be an artist, just live his life! We don't care."
Hartsock said she's been experiencing different food cravings daily, however, she's been feeling "pretty great" recently now that she has entered her third trimester. In the beginning, "it was pretty rough," she admitted.
Hartsock officially found out she was pregnant during a February vacation with her husband in Maui. Since then, the mom-to-be has reportedly reached out to former The Bachelor bachelorette Renee Oteri -- who just welcomed her third child on August 10 -- for advice.
"I love how relaxed she is; she makes it easy. If you don't stress about stuff, it comes easier," Hartsock said of Oteri.
Siegfried proposed to Hartsock during The Bachelorette's Season 9 finale, which was filmed in May 2013 and aired three months later on ABC. She selected the former pro ball player over runner-up Drew Kenney after getting over the heartbreak of frontrunner Brooks Forester unexpectedly dumping her.