Brad Pitt has reportedly spent over $80,000 on a home for his children’s gerbils.

The Inglourious Basterds star, who raises six children with partner Angelina Jolie, oversaw the construction and design of the project, which boasts tunnels, platforms, seesaws and mazes.

“Brad pores over architectural journals like other people pore over newspapers. He had so much fun putting the run together with his kids Maddox, Zahara, Shiloh and Pax,” a source told Britain’s The Sun newspaper. “It’s incredibly complex and cost a lot but Brad’s more than happy with any activity that can combine his two passions - his kids and architecture.”

The rodents - who will live at the family’s mansion in the South of France - were chosen by Maddox and Pax after their parents took them to a local pet store last week. “The boys were really keen to get the gerbils and it was Angelina who reached into the cage to pet them before a store worker got them out,” an onlooker said.