A spouse admitted in E-2 dependent status is employment-authorised incident to status. Children may study but may not work, and dependent status is available only while they are unmarried and under twenty-one. E-2 itself offers no direct path to permanent residence for anyone in the household.
Two adults, two different roles, one shared limitation
Where both spouses are Canadian citizens and own the enterprise together, either can be the principal applicant, and the other can be included as a dependant. The dependent spouse is employment-authorised by virtue of that status, so a spouse who wants outside work is free to take it, subject to whatever licensing the occupation requires. Children can attend school at any level and cannot take paid employment, which is worth saying out loud to teenagers who expect to work in the family business over the summer.
The shared limitation is the one that shapes long-term planning: E-2 is a nonimmigrant category tied to the enterprise, renewable while the business continues to qualify, but it does not itself lead to permanent residence. Families who expect to stay indefinitely should decide early whether they are content with a status that can be renewed but never matures, or whether they should be looking at an immigrant category on a separate track.