Abuse??

UPDATE;:: 
So after A night of no sleep endless tears and cold shoulder from husband... i got up and acted very normal . I reported my step son and gave all his details and my daughters to the relavent agencies so she can get th help she needs and so does he. My husband flew of the handle bars but has since calmed down and has come to terms with what will happen next. Safe guarding has been put in place with him at school so other children r not at risk. He could be looking at an oral rape charge. My poor baby is going to be vigorously examined and questioned which will kill me but she will understand one day what I did was for her well being and to protect her. You here about these things in the news and you never ever think it would happen in your happy home. We r a broken family but I will pull us all through it. I'm a mother, a wife and a strong muvafuckin woman 🙌
Ps thank for all advice and comments and sorry to anybody who has. Been in this situation x
I'm so lost for words it's unreal. Tonight after finding my 3 year old daughter naked in her 10 year old step brothers room that he has been touching her and making her touch him. I called his mother she came and collected him straight away I couldn't even look at him, my 3 year old has gone into detail about what he did to her and makes her do to him using words a 3 year old wouldn't know. My husband already thinks his son is an angel who is far from it he is awful anyways and I have struggled him from day one. A year ago my then 2 year old had bite marks and scratch marks which she said he did but no one believed her. I did. Took pictures of the marks. The mum says she is going to get him help but my husband won't let me call the police. I don't kno what to do. I have 3 little girls 7 3 and 4 months .... is this going to destroy my marriage or am I over reacting??? I have no body to talk to as my husband is not the type of man I can talk to about this stuff and he is in complete denial??? Plz dnt be rude or harsh I'm broken and broken for my baby.