I'm not quite sure what you mean by family friendly. Assuming your boys sit and eat politely and order off the menu I would think you could take them anywhere at that age. Other than chains, I can't think of Paris restaurants with food especially for kids (quite the American invention). A couple affordable friendly places where I would take kids near the center include: Le Trumilou (84 quaie de l'Hotel de Ville,01.42.77.63.98 Open every day), family run and attracts mostly French dineres despite it's location near the tourist center. The Restaurant du Petit St. Benoit (4, rue Saint-Benoit, 6th, M : St. Germain des Pres, 01.42.60.27.92. Closed Sunday) serves simple old-school classics. At dinner it's full of American tourists, but the lunches are more pleasant and it's a bargain. Le Relais de l'Entrecote ( 4, rue Saint-Benoit, 6th, M : St. Germain des Pres, 01.42.60.27.92. Closed Sunday) is a very fun place where I have also seen families. They only serve steak and fries, but they are good. I have seen families at Fish La Boissonnerie (69, rue de Seine, 6th, 01.43.54.34.69. Closed Monday) which is a very good spot for seafood, though it is full of mostly Americans. I often see French families with even small kids out at creperies. I think the very best in the city are the Le Petit Josselin and Creperie Josselin, both on the rue du Montparnasse. I've eaten at Josselin with a 3 year old, no problem.