Question: What county shares a border with the county Erin is located in?

full_context: Document 1: Richfield, Washington County, Wisconsin: Richfield is a village in Washington County, Wisconsin, United States. The population was 11,300 at the 2010 census. The unincorporated communities of Colgate and Hubertus are located partially in Richfield.
Document 2: West Bend (town), Wisconsin: West Bend is a town in Washington County, Wisconsin, United States. The population was 4,834 at the 2000 census. The City of West Bend is located partially within the town. The unincorporated community of Nabob is located in the town.
Document 3: Waucousta, Wisconsin: Waucousta is an unincorporated community in the town of Osceola, in Fond du Lac County, Wisconsin, United States. Waucousta is located at the junction of U.S. Route 45 and County Highway F, north-northeast of Campbellsport. A branch of the Milwaukee River runs through the community.
Document 4: Wayne, Washington County, Wisconsin: Wayne is a town in Washington County, Wisconsin, United States. The population was 1,727 at the 2000 census. The unincorporated communities of Kohlsville and Wayne are located in the town.
Document 5: Erin, Wisconsin: Erin is a town in Washington County, Wisconsin, United States. The population was 3,664 at the 2000 census. The unincorporated community of
Document 6: Grant County, Wisconsin: Grant County comprises the Platteville, WI Micropolitan Statistical Area. It is in the tri-state area of Illinois, Iowa, and Wisconsin, and is crossed by travelers commuting to Madison from a number of eastern Iowan cities, and by residents of northern Illinois traveling to the Twin Cities or La Crosse, Wisconsin.
Document 7: Plat, Wisconsin: Plat was an unincorporated community and is now a neighborhood in the village of Richfield, Washington County, Wisconsin, United States. It is located at the intersection of Plat Road and Monches Road. It is 2 miles from the towns of Erin and Merton and from County Trunk Highway Q (County Line Road) and the Waukesha County and Washington County division.
Document 8: Polk, Wisconsin: Polk is a town in Washington County, Wisconsin, United States. The population was 3,938 at the 2000 census. The unincorporated communities of Ackerville, Cedar Creek, Cedar Lake, Diefenbach Corners, Mayfield, and Rugby Junction are located in the town. The town derives its name from James K. Polk, 11th U.S. President, who was in office when Wisconsin attained statehood in 1848.
Document 9: Township 6, Washington County, Nebraska: Township 6 is one of five townships in Washington County, Nebraska, United States. The population was 1,516 at the 2000 census. A 2006 estimate placed the township's population at 1,713.
Document 10: Colgate, Wisconsin: Colgate is an unincorporated community in Washington County, Wisconsin, United States, straddling the county line with Waukesha County. Colgate is located partially in the village of Richfield, and the town of Lisbon. Its ZIP code is 53017.
Document 11: Trenton, Washington County, Wisconsin: Trenton is a town in Washington County, Wisconsin, United States. The population was 4,440 at the 2000 census. The unincorporated community of Myra is located within the town.
Document 12: Washington County, Wisconsin: According to the U.S. Census Bureau, the county has a total area of 436 square miles (1,130 km2), of which 431 square miles (1,120 km2) is land and 5.0 square miles (13 km2) (1.2%) is water. It is the fifth-smallest county in Wisconsin by total area.
Document 13: Otsego, Wisconsin: Otsego is a town in Columbia County, Wisconsin, United States. The population was 757 at the 2000 census. The unincorporated community of Otsego is located in the town. The villages of Rio and Doylestown lie in the geographic area of the town of Otsego.
Document 14: Westford, Richland County, Wisconsin: Westford is a town in Richland County, Wisconsin, United States. The population was 594 at the 2000 census. The unincorporated communities of Bunker Hill and Germantown are located in the town. The unincorporated community of Corwin was also located in the town.
Document 15: Germantown, Washington County, Wisconsin: Germantown is a town in Washington County, Wisconsin, United States. The population was 278 at the 2000 census. It is surrounded by the village of Germantown.
ground_truth: Waukesha County
sub_queries: Erin >> located in the administrative territorial entity Answer: Washington County
Washington County >> shares border with Answer: Waukesha County