The couple announced the news today, revealing that two-year-old son Zion Rain is going to become a big brother in January 2018.
Both the Australian model and her American musician husband shared identical photos on Instagram, posting a stunning image of Nicole and Zion.
"Gary and I are so humbled to announce with will be graced with the presence of a daughter in 2018," Nicole wrote. "We cannot wait for her arrival and to extend the evergrowing love of our family 👼🏼 "
After welcoming their son in January 2015, the longtime couple tied the knot in April 2016.
Congratulations to the beautiful family, we can't wait to meet their wonderful daughter next year.