Eligible derivatives do not require an additional principal investment merely to join the principal. Whether someone instead pursues a separate principal case is a different assessment.
Distinguish accompanying family from another investor
A qualifying spouse and unmarried child under 21 may be eligible, subject to applicable CSPA analysis and visa availability. A project subscription should not be treated as automatically necessary for every family member.
Record birth dates, the petition filing history, and each family member's intended activities, then have counsel apply the CSPA calculation to the actual facts rather than relying on a general rule of thumb. Derivative eligibility reaches the spouse and unmarried sons and daughters who are under twenty-one at the relevant point, and the calculation of that age is technical enough that it should be assessed rather than assumed, because processing times feed into it. Where derivative status is sought for a spouse and unmarried children under 21, the governing records are civil documents, being marriage and birth registrations, translations where required, and each person's own passport and immigration history. Each family member’s file holds that person’s own eligibility evidence: passport, civil documents establishing the relationship, and material addressing admissibility, with certified translations where an original is in another language.