NTA , tell your parents you would be happy to change it, if only you had the money to do so. Tell them if it’s so important they or sister would have to pay, otherwise your not wasting the money you have saved for starting you life and own family together. If they don’t you won’t!! If they threaten not to come , tell them okay it’s their choice , but don’t think for a second that you will ever forgive or forget it!