Final RT PCR test for negative resut.

Dear sir, Myself, my wife, my father and mother all infected with covid and we are all recovering one by one. Date of First symptom and hospital admitted date shown below for your kind reference. Myself - first symptom on 19th May. Admitted on 25th May. Wife - first symptom on 31st May. Admitted on 5th June. Father - first symptom on 4th June. Admitted on 8th June. Mother - first symptom on 6th June. Admitted on 10 th June. It would be really grateful if you are able to answer me below question. 1. What is best date to take final RT PCR test..? To ensure that the result is negative. 2. After the result is negative for all family members, should I want to sanitize my house? 3. When can I bring my 7 year old kid to my house? Now my kid is in my cousin house from past 37 days. Regards, Dilip