No. The age analysis depends on actual dates, visa availability and the applicable individual rules. A general family description is not that calculation.
Use the person’s immigration facts
Eligible derivatives generally include a qualifying spouse and unmarried child under 21, subject to applicable age protection. They need no extra principal investment merely to accompany. Payment or a brochure statement does not automatically freeze age.
Birth certificates showing place of birth for every family member, current passports, marriage and any divorce records, and evidence of prior immigration filings that might already carry a priority date. Age is measured at a statutory moment rather than at filing, and the Child Status Protection Act can subtract certain periods from a child's age in defined circumstances, which sometimes preserves eligibility for someone who passes twenty-one during processing. 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. A birth, a marriage, a separation, a child's changed circumstances, a dependant's own immigration history coming to light — each can alter the position, and each tends to be mentioned casually months after it happens.