Im the principal applicant i received Medical Request IMM1017 but my sister who is dependent applicant did not received it. Plse help me what we will do now for her medical exam?
I don't understand what you mean by "secondary applicant". There is no such thing. There is only the Principal Applicant and that person's dependents.
If you are both being sponsored as dependent children, then your apps are actually separate. She will recieve a medical request when her app is processed.