She has been caring for her mother, and her (engineer) brother files her taxes via turbo tax. In 2007 this income ($41,000) was reported as "other income" on line 21 of the 1040 and no self employment taxes were paid. In 2008, 2009,
2010, 2011 and 2012 this same income was reported as schedule C self employment income and SE taxes were paid.The return was originally filed before April 15, 2008 and has never been opened up. She claims to have no idea she should have paid SE tax on the 2007 income until today when I told her so. Is she required by law to amend this return and pay the SE taxes that should have been due?