Talk to Eye Specialist on Both Eyes Operation Within 2 Month

My father both eyes became week so he had an operation 2 weeks back for 1 eye to put lense on it. Doctors have told him that he should do the 2nd eye Operation at least after 3 month , but since my father is going abroad next month , he is insisting to have the operation for the 2nd eye in this month. he is 53 years old and has Sugar bemari as well. someone told me that it's dangerous to have both eyes operation in 1 month so kindly guide us what we should do?! at least I can show your responses to him so he may change his decision.i really appreciate all your responses . thanks.