One of my friend recently came to the US with DV lottery. He has kids and spouse but stated that he was single while he came to the US. Now he wants to file a petition for his family. Would he be in problem if files I130 with his original marriage certificate?
It to me sounds like he committed fraud to come to the US, coz he lied to the USCIS stating he was single. Please let me know what you guys think.

Please provide a best possible approach that he could use to petition his family.