Potty training

Amber • SAHM to a beautiful, smart, energetic 2 year old boy and his newborn brother!!
My 19 month old son has been potty training for a while now, and recently he has started taking off his pull-up whenever he wets or poos. He doesn't tell us "potty" until he is peeing on the floor. Any ideas on what I can do to help him get to his potty quicker? He loves sitting on his potty and will use it almost everytime I put him on there.