It's a hot summer day, and 8-year-old Zak Ballenger and his 5-year-old sister, Alison, are doing something they've never done in Paris.
They're diving into the cold, murky waters of a city canal.
"I like splashing around," Zak says, "because it's hot outside."
His mom, Celina Ballenger, is a 38-year-old nurse. She says she couldn't afford a vacation this year.
"So we've come here because we can't go out of Paris," she says.