Not exactly sure where to put this, but a few months ago my brother asked me to be a photographer for his wedding.

I declined

After suggesting someone else, more appropriate and experienced, he asked me to hang around the background and take candids.

I'm sure there are wedding photographers amongst the users here, what would you suggest I do, from a pro's perspective?

Sure there'll be plenty of other family members with point-and-shoot is trying to catch at the moment themselves, would I be any more in the way that they would?

Obviously my number one priority is to stay out of the professionals way, especially considering that they're being paid good money to get it right.

Did I do the right thing in declining initially? (Never shot a wedding)
Should I decline the second request as well?