Legos are expensive. Anyone with children knows that the interlocking brick building system can become a large investment. Now a family in Grandville, Michigan, is wondering who would take thousands of dollars of the toys from their home.

Brian Richards has been a Lego enthusiast since he was 5 years old. He's passed the love of building to his wife and two children, WXMI reported.

But recently someone took the $7,000 collection, and he documented the theft online.

"The Lego itself isn't special but the memory attached with (building) together is," Richards told WXMI.

The collection was covered by insurance.

The thief or thieves took nearly all of the pieces, but they will have a difficult time building the kits to completion. They left one important thing behind -- all of the instructions.

They also didn't take any electronics, camera equipment or tools that were nearby, according to Richards' blog.

Now Richards is asking for anyone to watch pawn shops and Craigslist for suspicious Lego sales. He also has sent a message to the person who took his family's collection.