Revisiting Art. 992

Article 992 of the Civil Code of the Philippines says:

An illegitimate child has no right to inherit ab intestato  from the legitimate children and relatives of his father and mother; nor shall such children or relatives inherit in the same manner from the illegitimate child.

Paras speaks of the Article thusly on page 494 of the Civil Code of the Philippines Annotated, Vol. III, 2013 Edition:

And here's how the barrier is explained (page 495):

I think this barrier, when it relates to the relatives (emphasis mine in Article 992, above), creates uncomfortable, complicated, and relationship-shattering   situations among would-be heirs.

Here's how Paras diagrams, on page 495, a relationship that can lead to several situations:

I can understand the barrier between B and C, between D and E, and between F and G if the inheritance comes from either side of the relationship.

But I don't seen any reason for a barrier between E and A if the inheritance is from A to E or the other way around.

Paras even considers an extreme situation (page 499):

Here we have a granddaughter whose misfortune is that her mother was a single parent and, in fact, the only child of her grandmother. We have laws protecting the rights of a single parent, especially an unwed mother which render obsolete the part of Article 992 talking of relatives.

In Lorrente v. Rodriguez, however, the unwed mother had other siblings. The siblings using Article 992 deprived their niece from what she would have inherited from her grandmother by way of representation. Can you imagine the resentment of the niece against her uncle? Article 992 in this case created an unwanted barrier.

I maybe inclined to believe in the barrier if it was a grandfather, father, grandson situation. There is no telling, without DNA evidence, that the grandson is a blood relative of the father's siblings. But in a grandmother, mother, granddaughter there can be no doubt, if you catch my drift.