To the extent the authorized trustee does not provide otherwise:
(1) the distribution of all of the principal of a first trust to a second trust includes subsequently discovered assets otherwise belonging to the first trust and principal paid to or acquired by the first trust after the distribution of the first trust's principal to the second trust; and
(2) the distribution of part of the principal of a first trust to a second trust does not include subsequently discovered assets belonging to the first trust or principal paid to or acquired by the first trust after the distribution of principal from the first trust to the second trust, and those assets or that principal remain the assets or principal of the first trust.
Official text of the Texas Property Code as published by the Texas Legislative Council.