The loss of a child is heartbreaking. My condolence, to your cousin. Memory trees represent the person. Any item can be placed on tree. Example would be starting with child's birth,a rattle or teddy bear,words attach a satin ribbon to item and place on tree. year one,a pair of baby shoes,left white or painted gold, attach a white satin ribbon.Use items representing different ages of child. Could be a pair of earrings,place in a sheer fabric bag with a ribbon. A necklace,favorite stuffed animal,toy,doll etc. Tree could have all white lights with white ribbon on items or colored lights with different colored ribbon. Use photos along with items. Any item that has a special memory for your cousin,it is her daughters' memory tree so anything can be placed on it that makes her feel comforted.