Request #409 From Barb

I read this book sometime in the mid 1900s-early 2000s, but it could have been published earlier as it was from the library . It was science fiction. Could have been adult or young adult. Girl is on a vacation with her family on a planet. Her brother and younger sister are there too. All three are kidnapped by aliens. The girl ends up being kept by an alien who is a scientist. The son ends up in an alien zoo and I think the youngest daughter became a pet of a “rich” alien…thing? The eventually break out and get home. Any bites?