Musnad Ahmad 626:48

Isma'il narrated to us, Yunus informed us, from Ziyad ibn Jubayr, from his father, that al-Mughirah ibn Shu'bah said: "The rider travels behind the funeral procession. The walker walks behind it, in front of it, to its right, and to its left, nearby. And the miscarried fetus is prayed over; supplication is made for its parents for well-being and mercy." Yunus said: "And the family of Ziyad mention the Prophet, may Allah bless him and grant him peace, but as for me, I do not memorize it [as being attributed to him]."