A spouse and unmarried children under twenty-one are derivatives. Adult children, parents and siblings are not, and each of them would need an independent basis with its own requirements and timeline.
The exclusions deserve as much planning as the inclusions
Families often plan around who is coming and give little thought to who cannot come on the same petition. Parents are outside it entirely, which matters in households where an older relative depends on the family. Adult children are outside it, which matters where a twenty-two-year-old expects to move with everyone else. For children approaching the boundary, statutory provisions exist that can in defined circumstances protect a child's age during specified periods, and their application depends on the facts and on visa availability, so the calculation should be done by someone qualified rather than estimated. A family with a child aged sixteen or older, or with a relative outside the derivative categories, should raise both at the first consultation.
Hypothetical example: Rafael plans an immigrant-investor filing with his spouse, an unmarried child aged nineteen, and a married child aged twenty. The first review should list each relationship and age, then verify the documents that establish them. Marriage and birth certificates settle the derivative relationship; marital status and age determine who can use it. The family must decide early whether the older child needs an independent immigration strategy rather than assuming the investor’s filing will cover everyone. Another mistake is delaying civil-record corrections until a visa stage, when inconsistent names or late evidence can interrupt an otherwise orderly family process.