Question re: Intestate Succession and per stirpes vs. per capita

I have a question about the Texas Intestate Succession Law.

It’s my understanding that when a person dies intestate, without a living spouse, children, or parents, then their estate will pass to the brothers and sisters of the intestate, and their descendants.

Here’s the question: when the brothers and sisters are deceased, does the estate pass to the nieces and nephews per stirpes, or per capita? One website I have found on this subject states,

" * Survived by descendants and no spouse: In this case, the deceased person’s descendants will inherit the entire probate estate, [per stirpes.]"
(The Definition of Per Stirpes in Wills and Estates).

When I read the Probate Code itself, it doesn’t go so far as to say “per stirpes.” It merely says: “3. If there be neither father nor mother, then the whole of such estate shall pass to the brothers and sisters of the intestate, and to their descendants.”

So, what does the Probate Code stipulate, or does it? Is it the choice of whomever is doing the title opinion, to do per stirpes or per capita? Is there one right answer, or two possibilities? If two, what guidelines are used to make that decision? Does precedent come into play, or have any bearing?

Thanks to all who can help me figure this out.