Answer:
It shows that he was convinced that Fred (his son-in-law) was capable of running the project, in addition to believing that family businesses are successful.
Step-by-step explanation:
Edwin and Fred made a strong friendship, which made Edwin trust and admire Fred a lot and his abilities to do a job well done, honest and successful. When Fred married Edwin's daughter, that trust and friendship became even more established and made Edwin see Fred as a member of his family, which was perfect for him to hand the inn project over to Fred and leave the business will be run within his family.