Here are the only boys names DH and I agree on for DC4, not sure they sound right with our surname Owen though.
Seth - DD thinks it sound like Slytherin?
Robin - too many 'in' sounds?
Theo - too many 'o' sounds?
Jude - potential for Judo?
Middle name will be Robert unless of course we go for Robin.
Other contenders are Isaac, Liam and Harry which I think sound better with Owen but also they are a very, very popular round here.