Mum's new car

Over the weekend I've been driving dad's car for work instead of driving my mum's Peugeot.
Thing is, my mum recently got a new car, a Lexus as well. She initially wanted a Mercedes, which was kinda pricey and I wasn't really keen of having her switch a car considering my brother jsut went to Aussie and the current economy is unstable.

But then how do you say no to "I worked hard for you and your brothers when you were born, now I'm aging, time to get something to pamper myself"??? Can't be a bad son and deprive her of her happiness right?

Like Colin said, "Kai Xin Jiu Hao"