Sebastian the Seahorse is a "Thought Detective". Sebastian reminds us to always look for the evidence about whether a thought is true or not.
An example may be that the thought is, "Nobody loves me". When looking for evidence you may find that one person was unkind, but mum and dad told you they loved you before you went to school, and your other friends are being nice, so the evidence shows us that the thought, “we are not loved”, is untrue and we need to change it.