3. Any adult husband and his adult wife and any adult unmarried person, who, as foster parent or parents, have cared for a child continuously for a period of twelve months or more, may apply to such authorized agency for the placement of said child with them for the purpose of adoption, and if said child is eligible for adoption, the agency shall give preference and first consideration to their application over all other applications for adoption placements. However, final determination of the propriety of said adoption of such foster child shall be within the sole discretion of the court, as otherwise provided herein.
Foster parents having had continuous care of a child, for more than twelve months, through an authorized agency, shall be permitted as a matter of right, as an interested party to intervene in any proceeding involving the custody of the child. Such intervention may be made anonymously or in the true name of said foster parents.