Yes, she had three - one boy who was adopted out, then Michael, then the third - a girl who was raised by a loving adoptive family. She was recently located and submitted DNA.
If memory serves, didn't the girl read the book with her mom and then they contacted Matt? Too much info to keep it all straight anymore.
ETA- I also agree with Cubby, one day technology will catch up with Floyd and I can only hope it is in his lifetime so he can pay for what he did to Sharon.