When you enable My Photo Stream on your devices, all new photos you take or import to those devices will be automatically added to your photo stream.
iOS devices: New photos you take are automatically uploaded to your photo stream when you leave the Camera app and are connected to Wi-Fi. My Photo Stream does not push photos over cellular connections.
Macs: Any new photos you import to iPhoto or Aperture begin uploading automatically when you have a Wi-Fi or Ethernet connection. Or you can change your iPhoto or Aperture preferences so that only photos you manually add to My Photo Stream are uploaded.
PC with iCloud Control Panel 2.0 or later: Open a Windows Explorer window and under Favorites select iCloud Photos if you are using iCloud Control Panel 3.0 (or Photo Stream if you are using 2.0 to 2.1.2). Open My Photo Stream. Click the "Add photos" button. Select the photos to import to My Photo Stream, then click Open.
For me, the answer to the question is between 30 seconds and a 1 minute, if I have iPhoto open and looking at my photo stream. What does the fact that your devices are ten feet apart have to do with iCloud (which is not ten feet away)?
Just to add...being 10' apart doesn't matter. The pics are sent to iCloud first and then back to iCloud devices. Most of the time it only takes a moment.
Sometimes it can be longer. A few days ago I took a couple of pis on my iPhone and wanted to upload from my Mac. After about 5 minutes I Messaged them to myself and got them right away. They showed up in my Photo stream a couple of minutes later.