When I was a kid, we had these little bird shaped whistles to which you added water. When you blew in them, they made a warbling sound. Ours were hard plastic, solid colored, and not the most attractive. When I saw these cute bird shaped water whistles at a local art musuem, I snatched them up for spring. I put them in my children’s Ostara baskets and they could not have been more thrilled.