Today Katie visited the Netherlands quite unexpectly.
She attended the christening of the son of Prince Pieter Christiaan and Princes Anita.
Their son is called Pieter Anton Maurits Erik van Vollenhoven.
Since the marriage of the royal couple has Katie become a close friend of them.
During the ceremony Katie did perform 1 song, Thank You Stars.
A tv team has interviewed Katie and hopefully recordings of that will show up.

Source Pic 1 en 2
Source Pic 3 en 4

Edit:

Here you can find a short video. Katie on 00:52-00:57s
Another record can be found here. Katie on 35:10-35:45