Casey is making major progress - so here's my question UPDATED

We got her last Saturday and she has been making MAJOR progress with her training. This morning she did not pee in the cage overnight and knows pretty much to go outside for #1 and #2. We are having a little trouble with nipping but i guess thats normal bc she is trying to play - we are working on that. My 2 cats have come out of the basement lol and will be in the same room as Casey and will look at her but won't go near her!

My DH wants to go to stay at his Dad's this weekend. He wants us to bring Casey - here are the issues:

1) It takes 5 hrs to get there and she is not used to being in the car...esp for not that long.
2) I dont want to disrupt her routine - for training purposes..
3) My FIL has 2 little dogs who pee in the house (yes, his stepmother puts paper on the floor and they pee- they are full grown )
and I dont know how Casey will react to them and I think they are a bad example lol
4) My IL's are a bit sloppy to put it mildly and there is crap all over the floor, i dont want Casey eating random things....

what do you guys think?

ETA: we are going much to my dismay. My DH said his dad has been looking forward to going fishing etc.... I feel bad bc DH hardly gets to see his dad and I have to go because i always do and I dont want to hear the comments.....but this sux!

on the way there just make a pit stop. or a few if needed. in the car theres not much room to circle around sniffing... my one dog always cries at the window when she needs to go out... even when she was a pup...
as for the two little dogs, thats fine. are you not putting paper down at your home for Casey? or did you go straight for the outdoors? Its easier with big dogs than little dogs to skip the paper training. as for the mom leaving down paper for her tiny ones, thats not 'bad' ALOT of people do it. When I'm not home I leave paper down and mine are full grown. they have tinier baldders and can not hold it as much s big dogs... and they know ONLY go on the paper/wee wee pad.
I dont think its a good idea to leave Casey home. 5 hrs there, 5 hours back. i dont know how long youre staying there but thats too long for a dog to be home alone. especially a puppy. (then again i dont know if you have someone going in there to help out) I figure Caseys gott a learn one day right?! why not start young.....

thanks guys

i know its not bad for little dogs to go on the paper in the house but it is when you leave pee and poop there for hours and hours and it is in the human bathroom, so who really wants to use that after thats been sitting there??