When Mimi had that abortion, & Rex found out, he got ticked and left her. That is when I believe she got married to Shawn, Belle married Philip, both females decided to have in vitro, and the Black Glove (EJ) did all that switching of eggs, sperm, etc. At that time, Mimi was using a surrogate, since supposedly she could no longer have children, and little Tyler was born. However, Mimi & Philip (who were now determined to be the parents) decided to give Tyler to the surrogate, neither wanted him, the surrogate could not care for him so left him at the hospital, where Kayla found him, called him Pocket as he was so small. Well, she & Patch wanted to adopt this baby boy, however, he went to another couple.........I think who lived in Indiana. I know viewers found it so hard to fathom that either one would give that baby up. However both Mimi & Philip left the show at that time, so.....we never heard any more about Tyler.