Doyle uses contrast a lot. Often he employs it to show that Paddy is fortunate to live in a family who encourage him educationally, provide him with nutritious meals and ensure he is clean and well clothed.
There are many references to the problems in Liam and Aidan’s family, with Mr O’Connell letting them stay off school as a treat and giving them takeaways every night.
In contrast to this we see Paddy’s mother providing a home cooked meal every evening - even when her marriage is falling apart - and both parents ensure that Paddy reads and does his homework.
This is one example of how Doyle highlights the high standards of care Paddy receives, despite the Clarke’s working class status and family problems.
This is reinforced when Paddy is in the medical room with Kevin. Paddy is initially embarrassed about the safety pin holding up his trousers. But then he reflects that at least he - unlike Kevin - has clean underwear.