Why my Ex is and Ex

Last night my son went to his dad's house. His dad drops him off in the morning when he goes to work so Trent can get ready for school. This morning I texted my son to see if he was on his way home.

Son: No

Mom: Why

Son: because

Mom: Why

Son: Have to help dad move

Mom: No, you are going to school

Son: No, I'm not...click

I called him up and said that he needed to go to school. Trent starts crying saying no, he isn't because his dad has to move by himself so Trent has to help him. I said no, you need to go to school. Click. He hangs up on me. I am already pissed by then. I called his dad's phone and left a message that he needs to get to school, that he can help him move after school or on the weekend. I called Trent's phone and said that he needs to get to school. He hangs up again. I called back and he answered. I told him to hand the phone to Ex. I told Ex that he needs to go to school today. Ex said that he needs help moving, Christina (his girlfriend) has to work, his dad is disabled, I don't know where his mom was and his uncle has a bad back too. Ex had to beg to get today off. Oh, he lives in a house with his mom, dad, girlfriend and her 2 girls and they can't afford to pay their bills. I thought his parents were supposed to move last weekend but apparently they all wait until the last minute to move. I told Ex Trent was planning on coming over this weekend to help move and Ex said that they had to be out by this afternoon. I know that the weather was kind of crappy yesterday but if I had to be out by today I would have been moving last night. I just don't get that family at all. They knew that they had to move so why they didn't do it throughout the week or start even last weekend!