Short answer. Yes. Article 196 of the Family Code makes no distinction between full-blood and half-blood siblings in the duty to support. Brothers and sisters, whether of the full or half-blood, are bound to support each other to the full extent the law provides — the degree of blood does not reduce the obligation.
What the law says
Brothers and sisters not legitimately related, whether of the full or half-blood, are likewise bound to support each other
Family Code, Article 196 — Support Between Siblings. Read the full provision →
The rule: half-blood siblings are treated the same
Article 196 of the Family Code is explicit: brothers and sisters not legitimately related, whether of the full or half-blood, are likewise bound to support each other to the full extent the law provides for siblings, except only when the need for support of the brother or sister, being of age, is due to a cause imputable to the claimant's own fault or negligence. That phrase closes the door on the argument that a half-sibling is owed less. Both share one biological parent; both carry the same statutory right and duty of support.
What sibling support covers
The Family Code defines support broadly for siblings just as it does for parents and children: everything indispensable for sustenance, dwelling, clothing, medical attendance, education and transportation — in keeping with the financial capacity of the family. The amount is not fixed; it is proportional to both the need of the sibling asking and the means of the sibling asked. If your half-sibling genuinely cannot support themselves and you have the capacity, that obligation exists regardless of whether you share both parents or just one.
The one exception: self-caused need
The statute carves out one situation where the duty does not apply: when the sibling of age needs support because of a cause imputable to the claimant's own fault or negligence. This means an adult sibling who is in need because of their own choices — squandering resources, refusing to work when able, or creating the need through their own misconduct — cannot invoke Article 196 as a matter of right. The exception exists to prevent the support obligation from rewarding irresponsibility. It does not apply to minors, and it does not apply to adults whose need arises from illness, disability, or circumstances beyond their control.
How this plays out practically
If your half-sibling is genuinely in need — facing serious hardship they did not bring upon themselves — and you have the financial means, the Family Code places a duty on you to help. The fact that you share only one parent does not diminish that duty. If the claim for support is disputed, the amount and terms can be determined by the court in a support proceeding. Support is also not static: it can be increased or decreased as circumstances on either side change. Whether you are the sibling being asked for support or the one seeking it, the law treats the relationship by the degree of kinship, not by whether both parents were shared.