hi all we have two grown up sons living at home, they are 20 and 19. when they started working we agreed to charge them £25 a week board. this wasn't based on what it costs to look after them or what we lost in tax credits but on what they earned. the oldest has a 0 hour contract and at first wasn't working much so was lucky to earn £100 a week. the other son had an apprenticeship at first so was earning just over £100. however the older son now works more and therefore earns more and the other son finished his apprenticeship and has a proper job, they both earn on average £200 a week. we have asked them to contribute more by upping their board to £40 a week. is this unreasonable? DS 1 is ok with it but DS2 informs me hes going to move out and live with a friend as hes not paying £40 a week to live in the house he grew up in.