While local authorities kept mum, a spokeswoman for Michelle Obama confirmed Monday that the first lady is in the Willamette Valley this week to visit her brother, Oregon State University basketball coach Craig Robinson. An airplane carrying Michelle Obama — who is Robinson’s younger sister — touched down Monday morning at the Eugene Airport. Semonti Stephens, the first lady’s deputy communications director, said Obama is being accompanied on the trip by one of her two daughters. Stephens said she could not say which of the girls came to Oregon with her mother, or disclose the length of their planned stay....