^ I keep thinking of the baby in The Begotten. Its first unprompted shapeshift was a primitive copy of Odo's face, and it copied him when he tilted his head to look at it.
Doctor Mora said Odo "told" him he was an intelligent lifeform by copying the beaker he was in.
That was a very good Odo-centric episode, and was a little reminiscent of TNG's The Offspring. It always made me wonder if the Founders actually intended for the infant changeling to die all along, or simply restore Odo's shape shifting ability.