CTH, just a suggestion to ease your travel out of the country with the girls.
Make sure you get a signed, notarized letter with your XW signature that states that you have her permission to leave the country with them. Google "Single Parent Travel" and you will find links to form letters you can just fill out and both sign in front of a notary. Canada and Mexico are very stringent on protecting children from being kidnapped by a parent and your court decree of divorce doesn't cover specific vacation times. I've seen people turned away without that letter and some go through no problem. It just depends on the agent at the border.
Another FYI - if you are driving into Canada you actually don't need passports, just birth certificates, but a passport is always a better option. You only have to have passports if you are flying. That law keeps getting pushed back.
T19 M15 S19 XH47 M43 bomb12/4/07 PA5/07 S12/26/07 D final 11/17/08 Back together with no defined R 05/2010 confused....to say the least!!!