Why Can't I file a single Green card petition for both of my parents?

Question

I do have a question regarding the Green-card filing of my parents. I am going through USCIS website here: https://www.uscis.gov/sites/default/files/files/form/i-130instr.pdf

Now, if I understood correctly, IF I am filing for my sister, for example, I am going to file for her and when she receives her green card, her husband and 5 years old kid would get it with her because they are her immediate family.

What I am failing to understand here is that IF my sister's husband is considered her family so that he can immigrate with her, why can't the same logic apply when it comes to my parents. That being I only apply for either of my parents and then since the other parent is an immediate family of parent1, they receive the green-card automatically?

I am just confused and curious. Any suggestions?

Answer 1

The reason is that the Immediate Relative category (spouse, parent, or unmarried under-21 child of a US citizen) cannot have derivative beneficiaries, whereas all other family-based categories, as well as employment-based categories and the Diversity Visa, can have derivative beneficiaries.

See 9 FAM 502.2-2(B)(d)(1):

The INA does not generally accord derivative status for family members of immediate relatives as it does for preference applicants. (INA 203(d) does not apply to the classes described in INA 201(b)). A U.S. citizen must file separate immediate relative petitions for the spouse, each child, and each parent.

The actual law for derivative beneficiaries in INA 203(d) (8 USC 1153(d)) says:

A spouse or child as defined in subparagraph (A), (B), (C), (D), or (E) of section 1101(b)(1) of this title shall, if not otherwise entitled to an immigrant status and the immediate issuance of a visa under subsection (a), (b), or (c), be entitled to the same status, and the same order of consideration provided in the respective subsection, if accompanying or following to join, the spouse or parent.

This applies to the categories in INA 203(a), 203(b), and 203(c). INA 203(a) are the family preference categories F1, F2A, F2B, F3, and F4 (all family-based categories other than the Immediate Relative categories). INA 203(b) are the employment-based categories EB1, EB2, EB3, EB4, and EB5. INA 203(c) are the Diversity Visa lottery immigrants. This does not include the Immediate Relative category, which is provided by INA 201(b)(2)(A)(i).