Ok. So my original answer below will change somewhat due to late breaking facts as past returns appear incorrect:
1) The TMP must be a GP. This should be changed as well.
2) My biggest concern here, based on the updated facts, is whether or not the allocation of income or loss has been correct in the past. Your initial facts indicate that you were designated as the GP, which means you were allocated the GP's percentage instead of your Mom. So my assumption is the past allocations have been incorrect.
3) Generally in a limited partnership the GP has a 1% interest. If that is the case here, then if the prior allocation was incorrect as noted above, then technically amended tax returns need to be filed.
4) Amending partnership returns is not as straight forward as other returns. Some just file a form 1065X, but that is not always correct. Generally, form 8082 should be filed and this form will set off some bells and whistles at the IRS. When filing this form and requesting an Administrative Adjustment Request, the IRS technically needs to respond with an approval or denial. This process adds a level of scrutiny that generally is best to avoid, but may unfortunately be the correct avenue.
5) The form 1065 definitely needs to be corrected for 2017.
6) The decision is yours as to how you will handle past years if the allocation was incorrect.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
