<prompt> Human: I helped self-prepare my parents taxes for 2016 where they had a decent refund due to claiming two of dependents, itemizing their deduction and reaping the education credits from my sibling, who was then attending university.Again, I am currently helping them prepare their 2017 tax return as married filing jointly yet again. This time, their previous two dependents are no longer dependents for 2017.Per TurboTax, effectively my parents owe 1,700 federal taxes due to their exemptions being reduced by half no more dependent claims. I am comparing their Form 1040 from 2016 to the current one in 2017 and that and the education credits are the only major differences I find, but its a huge difference. Obviously this is a huge surprise for us, so what steps should we take now? Am I overlooking anything? Is this normal?We can only deduct and get credit so much. Perhaps double check with another tax software? Not sure a CPA can do much to make the tax liability any better. We started self preparing in 2016 and we used their tricks to get the biggest refund we are entitled to. Any advice appreciated.  <response>: Seconded, its on the taxpayer to update their W4 to reflect losing the dependent exemptions. Sucks when it happens, but you gotta pay up. 