I was just wondering...

Agnetha and Peter's Album

I was just wondering who sings the song "På söndag" with Agnetha and Peter in their children's album.  The mysterious person is heard in the part when Peter sings about balloons and ice cream (You probably don't really know what I'm talking about because the song and album are in Swedish...) and is also heard singing the words På söndag with Agnetha and Peter at the end of the song.

Is it Micheal B. Tretow, ABBA's sound engineer?  I know he produced the album with Agnetha, so that could be it...  The person can also be heard in the song "Smurferifabriken", another song from Agnetha and Peter's album.  I don't really know what this song is about...  :P

I was also thinking about Agnetha's record company from during her Solo Career after ABBA.  The record company is WEA and there was a show called the Wea Road Show.  Are they related?  I know that someone from the Wea Road Show had been trying to interview her in a video, but that's all I know about the Wea Road Show.

Here is the video from the Wea Road Show.  I'm not really sure if it was fake or the guy - Peter the Producer??? - was really trying to interview Agnetha, but she didn't want to.

I'm sorry that the video quality is so bad...