Hi there, Toby sounds a wonderful friend.
Our Beagle Penny doesn't bark much either, only when playing or frustrated that our Corgi has her toy. But, boy when she does bark it is loud!!
Sounds like your Dad has a "soft spot" for Toby too! I don't have any advice to offer, as I am a relatively new Beagle Mother. I am sure other members will have excellent tips for you.