Finishing the tail

Connect the two tail pieces by crocheting around both the second and first piece:

Here's what you just did, written out in pattern form:

Round 4: 6 sc on the first piece. 6 sc on the second piece, starting with the stitch marked by the stitch marker (12)

Then crochet one more round:

Round 5: [4 sc, dec] x 2  (10)

Invisible fasten off, leaving a long tail:

Flatten the tail, and use the needle and yarn tail to sew the tail to the back of the body, directly across from the middle of the eyes and where you changed to the white yarn.