Complex Trust reporting

You are required to file a return for each entity (assuming here that each trust has its own TIN).

What if the same number for each Trust?  Both have same Trust Name and Trustee; but, two different accounts at Morgan Stanley started the same date.  What do I do?

It does not follow that since there are two different accounts at a brokerage firm (or more than one firm), there are two different trusts; one trust can have multiple accounts.

If you have one trust created by one trust instrument (trust document), then there is no need to file more than one return (if a return is required to be filed).