YOU SAID:

I have not been home in a dog's age.

INTO JAPANESE

犬の年齢で家に帰ったことがない。

BACK INTO ENGLISH

The dog is old and has never been home.

INTO JAPANESE

その犬は年老いており、一度も家に帰ったことがない。

BACK INTO ENGLISH

The dog is old and has never been home.