Yes, you can go for a combined mediclaim policy. But your in-laws need to go for certain tests because their age has crossed the age limit of 45 years to take the policy.
There are certain tests need to be done if somebody crosses the age limit of 45 years:-
Mediclaim examination as per the proposal form.
Complete blood count and ESR
Urine routine and microscopic
Cholesterol
SGPT
Stress Test
ECG
Serum Creatinine