Child custody laws in PA can a child be transferred from one school to the other without permission?

This is a long story... My fiances son has been living with us for a month now (although we ahve had him at least 3-4 days a week for 5 years) because his mothers husband killed himself... (after they broke up for a week) he was in kindergarden with her... since this happened he has came to live with us... transferred schools... and with us everyday... now she gets insurance money (after being on cloud nine that he was dead)... and now that shes done playing the grieving widow she calls tonight saying... i am moving into my new apartment this weekend and hes coming to live with me on monday and start a new school... i guess this is more of a legal question... in the state of pa... can she pull him out of one school and put him into the other without the fathers consent... he signed him in... is there an emergancy thing we can file tomorrow at least till we go to court for this... there is no need to uproot this poor child again?