The 28-year-old singer, who has a daughter Alaia-Mai, said he wants to provide their baby daughter with a sibling, reported Contactmusic.
"I would love three or four kids, but I don't want to put a time on it," he said.
Humes, who is busy working on the band's upcoming farewell tour, is finding balancing work commitments and family difficult.
"We're lucky that both of our parents live nearby and we can get help from them. Rochelle and I are both so busy but we're managing to juggle it," he said.