Old video of when my cat had kittens and Acey was being very gentle with them. First I introduced them to her with a muzzle but soon saw she was only interested in cleaning them like she would have her own puppies. There were never any problems though I still only let them be together when I was supervising.
Sighthounds can definitely live together in a house with cats if introduced early, they just take them as small pack members. Although when they are outside, cats immediately turn into prey that is fun to catch, so never let the cats outside with your sighthound.