Since I've been off waiting for our new little man to make his appearance, nap time and bed time…

Since I've been off waiting for our new little man to make his appearance, nap time and bed time have been a nightmare with my 2 1/2 year old! I thought maybe he was just out growing his nap so I tried keeping him up but by 4pm his is screaming and melting down about everything! Also over tired so he wont settle at night....what do I do! I need his sleep schedule figured out before the baby comes or I'm going to go crazy! HELP!