Yes. The spouse of an E-2 investor is employment-authorized incident to status and may work for the brokerage or any other employer once admitted. Children under 21 may study but may not work in the business.
The spouse's wage helps the business; the children's cannot
Hypothetical example: the investor's husband has dispatched for a carrier for years and would be the brokerage's first operational hire, and their 19-year-old wants to work the phones over the summer. The husband may be employed by the brokerage as an E-2 spouse, with the annotated I-94 as evidence of authorization, and his wage appears on the payroll that helps show the enterprise is more than marginal; officers do sometimes discount a spouse's role when assessing whether the business supports more than the family, so plan additional hires beyond him. The 19-year-old, admitted as an E-2 dependant, may not be employed by the brokerage or anyone else, paid or unpaid in a way that displaces a worker, and his dependant status ends at 21. If he wants to stay beyond that, a student status or his own route must be arranged. The family applies for E-2 visas together at the consulate, and each admission follows the principal's.
Hypothetical example: a Canadian investor opens a small stained-glass restoration studio and hopes her spouse's wages will carry the household while the business develops clients. Family budgeting does not cure an inadequate enterprise case. The file must show capital irrevocably committed and at risk, an investor who will direct the studio, and a real business projected to be more than marginal. The decision is whether to fund the planned employee and marketing work now or postpone filing until those commitments exist. Dependent documents should be prepared only after the principal's commercial record is coherent.