If you need to generate two Schedule K-1s, report a change in ownership, and add the new member. Be careful entering the date when the change occurred. You may need to calculate the income/expenses before the change so you can allocate only that portion to the deceased member.
In the end, you should have one K-1 from the beginning of the year until the change of ownership. The other K-1 will report only the activity after the change.
This is a complex and tedious process, and you may consider upgrading to TurboTax Live Assisted Business. This online service provides step-by-step guidance from a tax expert whenever you need assistance, either over the phone or by screensharing.