Your parents will be ok with both you and your sister marrying same guy.
Best way to finish an argument is "ek second" and then go on a mahaan rant or don't say anything at all and cry silently in the coner.
Its more important to be right than to consider the feelings of your spouse.
Its okay to donate your first-born.
You are responsible for the well-being of everyone in your life and thus have to scarfice everything silently or else they can never be happy.