Facebook read our mind?

Last night I’m deaf I sign language to my wife about how to keep bread fresh in sign language we do not use voice or use type on phone at all and we went to bed immediately after talked in sign language. Next morning I got ad on Facebook about food seal with vacuum that I was talked about in sign language to my wife. How did Facebook read my mind or sign language in my own house?

bread facebook food language next phone privacy sign vacuum voice wife