It means your dog was put down and there was a raven in your garden......
It means your dog was put down and there was a Raven in the garden when you got home; nothing more. Sorry for your loss, by the way.
It means a raven was coincidentally in your garden after your dog was put down. RIP.
It means that there was a raven in your garden, nothing more. There will have been lots of occasions where various birds have visited your garden, it's just that you are looking for some kind of sign or meaning, probably for comfort, following your loss. I am really sorry for your loss by the way.
It means your dog has just been put down and there was a raven in the garden.
