I'm writing a short text and I got stuck because I wanted to write that my parents, who are now at home not working seeing that they retired from work, seem to be unhappy. Can I say something like: 両親は働かないで嬉しくなさそうです?
I would use 〜みたいです。みたい can be used to express your opinion or assumption based on what you have seen first hand. “It looks like”/ “It seems like”. そう I believe is more commonly used for things you've heard.