Letter for children traveling with out one parent???

I know that there is letter that I need when taking my children to PV without their father. I am hoping that someone can help me find a link for this letter. The last time that I took them I found the letter on this site. Can someone please help me?? We will be leaving in 3 weeks and I still need to have it notorized. Thanks in advance for any help that can be provided.
:shock:

I also will have to get a letter made up for Connor and I for Feb. Connor already has his passport. I wonder if a letter written by his mom allowing him to travel out of the country, and then notorized will be sufficient.