Orphans -- Juvenile fiction. Robots -- Juvenile fiction. Rockets (Aeronautics) -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction.

Space ships -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Unidentified flying objects -- Sightings and encounters -- Juvenile fiction. Space flight -- Juvenile fiction. Families -- Juvenile fiction.

Human-alien encounters -- Fiction. Space colonies -- Fiction. Interplanetary voyages -- Fiction. Space warfare -- Fiction.

Xenomorphs (Fictitious characters) -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Twins -- Juvenile fiction. Space colonies -- Juvenile fiction.

Princesses -- Juvenile fiction. Impersonation -- Juvenile fiction. Kidnapping -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction.

Life on other planets -- Fiction. Human-alien encounters -- Fiction. Interplanetary voyages -- Fiction. Spiders -- Fiction. Survival -- Fiction.

Human-alien encounters -- Juvenile fiction. Kidnapping -- Juvenile fiction. Space warfare -- Juvenile fiction. Princesses -- Fiction. Impersonation -- Fiction.

Human-alien encounters -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Friendship -- Juvenile fiction.

Camping -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Scully, Dana (Fictitious character) -- Juvenile fiction. Mulder, Fox (Fictitious character) -- Juvenile fiction.

High school students -- Juvenile fiction. High school athletes -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction.

Extraterrestrial beings -- Fiction. Life on other planets -- Fiction. Human-alien encounters -- Fiction. Science fiction.

Teenagers -- Juvenile fiction. High school students -- Juvenile fiction. Superheroes -- Juvenile fiction. Ability -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction.