What does everyone use for toddler sleeping while travel if they're too big for a pack and play but not ready for a bed yet?

When we go to my parents' house we usually use the pack and play but my 19 month old DD can climb out of the pack and play. My mom won't let her sleep in there anymore and is giving us the option of either a mattress on the floor or a toddler bed. Pediatrician agrees she's not ready for a bed yet since it'll open up a whole new set of sleep problems, and she'll just get right up and start trying to get out of the door.

I'm stumped.