Different citizenship is not by itself a general bar to a qualifying spouse’s derivative case.
Review the actual relationship and case conditions
Eligibility, admissibility, age issues for children and applicable availability rules still matter. Do not infer that identical passports guarantee eligibility or that different passports automatically require exclusion. Eligible children generally must be unmarried and under 21; assess any applicable CSPA protection on the individual case facts.
Confirm which specific family members meet the official definition of an eligible spouse or child before including them in the budget or application, rather than assuming a broader family group can be included together. Record each proposed joining person’s identity, relationship, date of birth, marital status, current location, passport, and possible visa-availability issue. List each person the case actually covers, mark whether they are a legally married spouse or an unmarried child under 21, attach the document that establishes it, then apply the published per-person amounts and compare the result with the demand. An intended spouse or unmarried child under twenty-one who was not actually included at the outset is not included by virtue of living in the household, and adding someone later is its own question on its own terms.