My mom passed away in September. She did work until the end of February and then she retired. She was getting social security after that. I have the 1099's for both. Should I file taxes for her? She did her taxes online on my computer so I have 2006's taxes. I'm the successor of the trust and I want to make sure I'm handling everything correctly. Thanks

Yes, you must file the tax return if she meets the filing limit or there is a refund. If there is a refund, you will also file form 1310. On the top of the return write Deceased and date of death.