The 38-year-old singer announced the news via social media.
"So the Mclean family will be expecting a new addition to the family next spring!! #laborday! Ha get it 'labor' day! I'm a goof! #avaisgonnabeabigsister #baby2! Keep u all posted!! We're so excited," he wrote on Instagram.
Rochelle also shared the update on Twitter.
"*THEN there were FOUR! Cats out of the bag! Couldn't be more excited to add another little to our family! Baby McLean #2 spring 2017!" she wrote.
McLean and Rochelle, a hairstylist and makeup artist got married in 2011.