In Aetna Insurance Company v. Naquin, 488 So. 2d 950 (La. 1986), a property insurer's suit against a contractor for reimbursement of funds paid to tenants on behalf of an insured landlord was consolidated with the insured landlord's suit against the contractor for alleged negligent performance. National Automotive Insurance Company cites Aetna for its description of subrogation, as follows: The granting of subrogation is completely compatible with the whole of Louisiana law. The insurer is not a mere volunteer who has paid the debt. Therefore he should not fit under the general rule of LSA-C.C. art. 2134. See now La. C.C. art. 1855. The Code recognizes that a person with an interest who pays in his own name and is bound with the other debtor ought to be subrogated to the creditor's rights against the other debtor, unlike a mere volunteer. This recognition is embodied in LSA-C.C. art. 2161(3). See now La. C.C. art. 1829. Subrogation is also consistent with Louisiana law concerning collateral sources. The "collateral sources" doctrine serves to prevent the defendant from receiving a windfall because the victim has chosen to provide, by contract, other sources of redress for injury. We do not permit this credit for the defendant because of the recognition that he is in fact liable for the harms so paid for by others. To the extent that others properly present their claims they should be reimbursed. (488 So. 2d at 954.)