Billy is a transition-year student at Gonzaga College, and Patrick is in sixth class at an Educate Together school. They live in Stillorgan with their journalist father Richard, and mother Kate, who runs the Grafton Suite business and market research centre. Acting is obviously in the blood, as the boys' dad Richard played the role of Herr Flick in the BBC comedy series, Allo, Allo.

Billy and Patrick can be seen in Maeve Binchy's Anner House drama on RTE One at 9.30pm tonight.

Billy on Patrick I was four when Patrick was born, and I remember going to the hospital and seeing him when he was born.

Patrick and I are very different, and we didn't always get along when we were younger. I'd be more on the logical side, because I love maths and science, and he's probably more creative. He plays violin, and is starting to learn the guitar. He's very good at magic tricks, especially at card tricks. I think he's very talented, and he has a very good voice, and he's also really good at art. I can't draw a thing.

We've both done some acting before, but Anner House was the first time we did something together. It was good working with my brother, and at least we could say whatever we liked to each other and it wouldn't cause offence. We went to Cape Town in South Africa for three weeks to film it, and it was really good. Our dad was able to take time off work to go with us, and then our mum came over at the end because she had to work, and we all went on holidays. We went on safari and stuff, and it was great.

We were on the film with Liam Cunningham and he played our father, an alcoholic who divorces his wife and goes to South Africa to work. Liam is great because he's incredibly professional, and he was very nice to us. He wasn't at all starry, and we learned a lot from him. I thought Patrick did really well on set, but even though he's younger, he's actually got far more experience than me in film work. He's been in Bye Bye Inkhead and Baker Street Irregulars and a Vodafone ad.

Being in Africa was disruptive in some ways to our lives, but it was grand for me because I'm in transition year at school, and my school is very encouraging. Patrick had to do some catching up, and he was supposed to make his confirmation this year, but he has to wait until next year now, because he missed too many religion classes while we were away filming.

When we were in South Africa, we didn't have our own friends with us, so we hung around together, which was great. It was nice that we both made the same friends on the crew, and Patrick got along great with a boy called Siya from South Africa.

I think we may have been picked for the film because we were so typical of everyday brothers. Our characters fight about very small things, and they're just like us, because siblings don't always get along all of the time.

Patrick and I get along well with each other now most of the time, compared to when we were younger, although I sometimes try to annoy him by singing loudly, which is what drives him mad about me. He's a good laugh, and he's very lively, whereas I'd probably be quieter and more serious.

Patrick on Billy I think Billy is a really good big brother to have. He's great at music, and won the 'best guitarist' award at the battle of the bands competition in his school. I think it has had an influence on me, because I'm in a band in school too, and I sing, and sometimes I play guitar. Billy is teaching me, and he's quite patient.

He likes sailing, and he's going to bring me out soon.

Billy helped me loads with my school-work in South Africa, because I had to do some catch-up work on fractions and stuff. My favourite subject in school is English, and Billy's is maths. He's always very interested if I try to show him a magic trick, but when he tries to show me something and I don't understand it straight away, he gets a bit annoyed.

Our personalities are different, because you couldn't always tell when Billy's really happy about something, because he doesn't spring around the place like I do . . . he's kind of cool and calm, but he's really nice as well. I think I talk a lot when he'd prefer me to be quiet, like when he's studying.

Making the film was really cool, and working with Liam Cunningham was brilliant, because he was really helpful to us on the set. We played two brothers, and they were pretty much the same kind of brothers that we are.

There was one scene where my arm ended up bruised, because Billy's character Eoin had to box my character Ruairi a bit, and when the director was saying we had to do another take, I was like, "Ah, please, no!" The director was saying to Billy, "You don't actually have to hit him!"

We were still speaking afterwards thoughf well, kind of!

It was great being in Cape Town, and the weather was brilliant. We were able to go surfing because the waves were massive and really scary.

We played cricket when we had to hang around between scenes.

I think I'd like to be an architect when I get older, because I like buildings, and we spent a good bit of time looking around too.

Billy took acting classes with Betty Ann Norton and the Royal Academy when he was younger and I took some classes too, but I was too young to remember them. He's going to be in the first episode of The Clinic soon, and he'll be in a few episodes of Fair City as Eamonn Doyle. He was very good at helping me to learn my lines for the film, and I think he's a really good actor.