She may work in the business as an E-2 spouse, who is employment-authorized incident to status, but her labour is not capital and her role does not by itself make the enterprise non-marginal.
The spouse can work; the spouse cannot be the investment
Spouses of E-2 principals are considered employment-authorized incident to status once admitted, so the consultant’s wife may handle administration, sales or technical work for the company or take employment elsewhere. Two limits apply. Her unpaid work is not an investment of capital and cannot be added to the US$150,000, and a business whose only workers are the two spouses is still a business supporting one household, which is the marginality problem in another form.
The hiring plan should therefore count employees who are not family. Unmarried children under 21 may accompany the couple in E-2 status and attend school, but they may not work and their status ends at 21. If the family later wants permanent residence, E-2 provides no direct route, and each member will need a separate basis.
Hypothetical example: the owner of a mobile pet-grooming company wants her spouse to operate a separate online shop after arrival. A spouse’s work authorization does not turn that shop into part of the E-2 enterprise, and its income does not prove that the principal business is non-marginal. The family should keep the ownership, banking, and tax records distinct.
Children may attend school, but every family member’s status still depends on the principal maintaining the qualifying enterprise.