Forget water. Blood is apparently not thicker than residential real estate down in Florida.

Developer Edward K. Buchanan learned that undoubtedly painful lesson last week after coming up short on the $12 million that he’d borrowed from his brother, Rep. Vern Buchanan (R-Fla.). According to trade publications, the interfamily loan was prospectively secured by a pair of vacant lots — 21 acres and 24 acres — Edward had pounced on in the mid-2000s.

When the economy started sputtering, Edward’s options apparently quickly dried up.

“When the housing industry fell on hard times, Eddie could no longer make the payments and returned the property to Vern,” a Congressional aide said of the land swap. The aide added that the lawmaker has no plans to capitalize on the undeveloped properties, what with much of the local housing market underwater.

No word on whether the recent repossession has in any way soured the relationship between the brothers Buchanan or whether this is simply business as usual.