This is what happened on Wednesday, May 9, 2007 in stories that can be dated.
Events[]
Stuff.[1]
Stuff.[2]
Beverly Hills, CA[]
At the home of Lisa and Megan Stone, after lunch, Megan notices that her mutation is giving her stripes on her back.[3]
If you're as bad at reading as this editor, "A couple days passed, and Megan’s improvement increased." is talking about the time from the 7th to the 9th, not that some impossible days passed from the 8th to the 9th.