The Brovarniks are now a party of five.
"SHE has arrived!!! We are so happy and proud to introduce Ariel Raya Brovarnik. Our baby girl was our anniversary gift, born September 6 at 11:40pm," Alexei captioned the post. "Finding out the gender in the delivery room was even more special than we could have imagined."
The video showed the reality stars in the delivery room alongside their newborn. In one of the photos, their daughter is seen holding on to her parent's finger.
Alexei also gushed about Lauren, his wife of 7 years, writing, "Thank you to my better half @lorenbrovarnik for making me the happiest man alive."
The Brovarnik family announced the were expecting their third baby in three years in an early Mother's Day post in May.
"We are so excited to finally say that baby #3 is on its way! We are going to wait to see if it's a girl or a boy, either way we are so overjoyed," Loren captioned the Instagram announcement. "Life will be crazy with 3 under 3, but we can't wait to meet you this fall, BabyB!"
However, the road to becoming a family of five hasn't been the smoothest.
"When Dr. Santos says that he can't breathe on his own and that he's intubated, it's scary," Loren said in the episode. "You're like, 'Oh my gosh, is he going to make it?'"
"I questioned," she continued, "'Is it my fault that he can't breathe on his own? Is it my fault he came early? Could I have prevented it? Could I have done something different? Like, what did I do wrong?'"