Thank you - I am appreciate the help. For the IMM 0008 - Generic application then, should my husband only write ONE for the # of family members in the application if he is the only one applying for PR ... and we wouldn't include our children in the DEPENDENTS section?
Correct; I believe if you read that section carefully, it says "who are not citizens or permanent residents" (or similar phrasing). I.e. this section is only for those dependents who are effectively applying to become PRs (or potentially could through spouse)*, and your citizen-children cannot apply to become PRs.
Note there may be a separate form that is background identification on your spouse - on that form those children would be shown.
*Important star for others who may read this - all dependents who are not already citizens/PRs may have to be listed here, even if the sponsor/principal applicant do not intend to bring them to Canada.