"What are you doing here?!" Oliver shouts as he sees his youngest sister Ashlynn swimming to shore with a man he has never seen before. Sydney knows exactly who Thomas is though. They dated all the way through high school and she finally decided to break things off after he unexpectedly proposed to her on the day of their high school graduation ceremony. Will Sydney tell Oliver about her past? Will Oliver focus more on his baby sis than his wife and child? #usisland #usislandchallenge