Taking cat(s) camping

I am going up to our camping property this weekend. I have taken one of my kitties before (she is 2.5 years), several times. She hasnt been at all this year however. We have a small trailer, she is always on a harness, and i do have an outdoor playpen if we decide to do that.

We got a new kitten in the spring and there has been some adjustment. The kitten is 10 months, almost the same size as my other girl, and super high energy, but sooo snuggly and affectionate.

I thought, since it is supposed to be rainy this weekend (the first in months) it would be nice to just huddle in the camper and have a chill weekend with her. It would also give her a break from the kitten.

Here's where I wonder though. Would my kitten feel left out? I do plan on taking her eventually, I just wonder if both at the same time is better than one at a time?