In the morning I was called to visit at Br[other] Samuel Smith's. His wife was confined an[d] in a verry dangerous situation. Br[other] Carloss took one of my horses and went to Chardon after Doct[or] [Frederick G.] Williams. I went out into the field and bowed before the Lord and called upon him in mighty prayer in her behalf. The word of the Lord came unto me saying, "My Servant Frederick shall come and shall have wisdom given him to deal prudently and my handma[i]den shall be delivered of a living child and be spared." He [Frederick G. Williams] come in a bout one hour after that and in the course of about 2 hours she was delivered. Thus what God had manifested to me was fulfilled every whit.
[Faulring, Scott (ed.), An American Prophet's Record: The Diaries and Journals of Joseph Smith: Joseph Smith Diary, 1835-36, http://amzn.to/jsdiaries]