Jami` at-Tirmidhi 1193

Al-Aswad narrated from Abu As-Sanabil bin Ba'kak who said:"Subai'ah delivered twenty-three or twenty-five days after her husband had died. So when she was ready (finished post-natal bleeding) she adorned herself for marriage, but she was rebuked for doing that, so it was mentioned to the Prophet and he said: "If she has done that then her time has come