A large Native American population at the Flat River made the area important to fur traders, and French and American traders came in winter to trade before returning to Mackinac Island and Detroit in summer. The earliest known post near the Flat River was the LaFramboise Post. Joseph LaFramboise traded on the Grand River as early as 1783 and established a post here in 1796, the same year he married Magdelaine Marcotte, a French-Indian woman. After Joseph was killed in 1806, Magdelaine, known as Madame LaFramboise, continued the business and became Michigan's first businesswoman. She worked as an independent trader until 1818, when she became an agent for the Mackinac-based American Fur Company owned by John Jacob Astor, and company records show she earned as much as $10,000 a year. The precise location of her post is unknown. In 1821 she retired to her house on Mackinac Island. Rix Robinson took over in the Grand River area for the John Jacob Astor Fur Company in 1822. Seventeen-year-old Daniel Marsac arrived in 1829 to begin trading, and in 1831 he built a log trading post at the junction of the Flat and Grand Rivers, operated it until 1846, and settled there. He first married an Odawa woman, Jenute; they had a daughter, Marie, whom he took to Detroit for education, where she soon became sick and died. Marsac later married a French woman, had 10 children, gave up trading, platted 80 acres as Dansville, opened a log tavern, and then left town to become a farmer. John Hooker purchased and continued to operate the Marsac Post from 1846 until the Indians relocated to Oceana County in 1857. Hooker, who spoke Odawa fluently, had helped his father build the settlement of Lowell, took over Marsac's post at 16, and later served as an Indian enumerator, taking an annual census so treaty payments distributed in Grand Rapids were fair to all. He remained a friend of both Indians and settlers.