My dad is useless

So my brother is in prison. Him and his friends were stupid during their teens years and got into trouble from stealing and trading cars hence why he's in prison

This may be lengthy but am I wrong for if I no longer see my siblings because of my dad?

Here's the story

My mum lives abroad. I live in one city for university and my dad and sister (14 years old) live in another city.
Me, my sister and my dad were going to visit my brother this weekend however to book the ferry to see my brother I need money. I fund my lifestyle so thats my rent food, transport etc. I have a loan of course but it's very stretched atm. Anyway I asked my dad for money for the ferry and he says no because has has rent to pay. My mum offered to pay however my mum pays for absolutely EVERYTHING except my stuff as I prefer to pay my own way through life when I can.

The ferry is only £40. If I don't pay it that means he'll refuse to go. I can't go on my own and neither can my sister which means a little sister doesn't get to her brother and neither do I. I would pay but I'm already paying for the train to go to his house and then paying him petrol to take me to the airport the day after we see my brother

My dad works 24/7 so I don't see why he can't just spare £40.

If i cut him off I won't be able to visit my sister and my brother. Is this justifiable? Obviously it's not but I'm so sick of him not pulling his weight. When my mum still lived here she paid for everything and even his stuff too. He's so selfish, I have seen how much he has in his bank and he has thousands

Having to deal with any financial matter when it comes to him is so frustrating. I don't mind waiting to visit my brother when I start driving however its not fair on my sister who has to miss out because her dad is such a bum