Catherine Giudici-Lowe is counting down the weeks until her second child arrives.
The former Bachelor alum, 31, shared a mirror selfie showing off her growing baby bump at the gym Friday on her Instagram Story.
“Baby is the size of a mango,” she wrote in the caption while holding a medicine ball up to her stomach for comparison. “19 weeks,” she added.
Giudici-Lowe also shared a Boomerang video of herself rubbing the ball with a loving look on her face.
“Pregnancy makes you do bizarre things. Like pretend a medicine ball is your baby and then document and publish it. @fit180dallas,” she wrote.
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The star and her husband Sean Lowe announced their pregnancy in November with a sweet clip of their 17-month-old son Samuel Thomas pointing to Catherine’s belly.
“Hey Samuel, can you say baby?” Sean says to his son in the video before Samuel points to Catherine as she giggled and said, “Baby!”
“Baba numba two,” Catherine posted on her own Instagram, sharing a photo of her lying on the couch with Samuel as he touches her belly.
In a separate clip Catherine shared, she asks, “Samuel, what’s this?” before he answers, “Baba,” pointing to his mom.
Sean and Catherine met on season 17 of The Bachelor, where they got engaged on the March 11, 2013, finale before tying the knot in a fairy-tale wedding that aired live on Jan. 26, 2014.
The couple’s upcoming addition isn’t a surprise. In September, Sean told PEOPLE that the possibility of baby No. 2 is “not off in the distance because Catherine wants a big family — she’s convinced she wants several more kids.”
“I’m 33 going on 34, so we better get crackin’ sooner or later!” he quipped, adding, “I would say that hopefully in 2018 we have another one.”