A Lisbon man who used his own child’s Social Security number in a scheme to illegally receive welfare benefits has been sentenced to four years in prison. Federal prosecutors say 34-year-old Mark Judd was also ordered Wednesday to pay more than $29,000 in restitution. Judd pleaded guilty in January to Social Security fraud, making false statements to a financial institution and aggravated identity theft. Authorities say from 2010 to 2102, Judd used his child’s Social Security number on job applications, then failed to report wages earned under that number to the Maine Department of Health and Human Services and the U.S. Department of Agriculture to illegally receive welfare and housing benefits. Judd also used Social Security numbers not assigned to him to open lines of credit at several financial institutions.