To answer your last question, you need to look for language stating that you have certain immutable powers and authority, for example, to vest the corpus, in whole or in part, to yourself personally. I strongly recommend that you consult with local legal counsel.
Your father was the grantor but not any longer as the trust became irrevocable upon his passing and is now a separate entity. Again, depending upon the language in the trust, you may be "owner" of part, or all, of the trust corpus.
Otherwise, with typical trust language, you would be trustee and beneficiary of a complex trust (i.e., one where the trustee has discretion to distribute corpus) and the trust simply has skip persons (or at least potential skip persons).
To reiterate, you need to have the entire document reviewed by a local professional (preferably a local estates/trusts lawyer) to ensure you are discharging your obligations under the trust in accordance with the terms.
