She may be Robert Pattinson's mystery woman, but she's still a full-time mom!
Well, full-time might be stretching it…
Sienna Miller was spotted dropping off her adorable daughter Marlowe with the babysitter on Wednesday.
Then she ducked into a cab and quickly sped away from the paps!
Why was she in such a hurry? Why so secretive? Was she heading off to a rendezvous with R-Patz? A clandestine encounter with clan Cullen's favorite son?
Nah! We're pretty sure the two are just friends.
[Image via Ramey Pix.]