Miniature of Duchesse de Chateauroux with child C1730

Round miniature of a mother and child, possibly Marie-Anne de Maailly-Nesle, Duchesse de Chateauroux, wearing a blue robe with white underslip and flower in her hair.  Her daughter is wearing a white embroidered dress with matching blue hat with a single ostrich plume.  Watecolour on vellum in the manner of Jean Marc Nattier C1730.  Gilded frame with solid reverse and watch top.