Found the report re: Ambha singing SOS. It was posted by our member CoolWater:
From the soundcheck on you could tell Brian was having a good day. When Mike's daughter came out on stage Mike walked over to Brian and said something to the effect of 'If it's all right she's going to sing Sailor tonight." Brian joked back saying "But that's one of my lead vocals." Mike's daughter was okay on "Sailor". Her singing was fine, but she didn't really connect with the words in the verses, but she hit the tag perfectly.
http://smileysmile.net/board/index.php/topic,13127.msg280436.html#msg280436