I watched this movie a long time ago.
But, basically, a widowed father has two socialite daughters. The older one is much quieter, more serious and strict. A man comes into their lives and is set up with the younger daughter, even though the older daughter obviously likes him (there's a lot of banter). She's ignored because of her age, demeanor, etc. Towards the end the man realises that he's actually in love with the older sister, who eventually becomes less strict etc. I think it was set in Italy. It was in colour.