No, the father does not have an insurable interest because he is legally not the owner. Use does not give someone an insurable interest: for example, consider a tenant in an apartment building--the apartment is his home, and he lives there everyday; but he cannot insurer the building (only his own belongings) despite his use and his need for the apartment, because he does not own it. It is the same in the situation: neither the father's use nor his need create an insurable interest.