I need help on what to do with my 8yr old nephew its so Improtant i get advice... plz?

My 8 yr old nephew loves to turn to lighters, matches, to make fire and wont stop we have tooken him to conculing, to the fire station to learn about it and have them talk to him. his dad has burt his figuers think and hoping it would work it didnt so now he living with him mother she doesnt knwo what to do with him either, I watch him before and after school and on the weekends. I dont trust him one bit, i dont know what to do with him at all, i cant him but it doesnt work either. so any advice i would be do happy to have any idea on what to do. thanks