Christmas Tip to Portiniera, normal in Milan?

Hello, I would like some feedback from the locals if it is customary to tip the doorlady at Christmas time. I live in a modest building (no lift, no lobby, no garden - lots of nothing) but it does have a woman who cleans the entrance and the courtyard and building area. She works very hard. It's a bit different from NY where my mother has doormen who do everything (collect mail, packages, arrange deliveries, get cabs,.....) There she tips a lot. So, do I tip a small amount, as a token of appreciation? Do others do this? I will probably tip something regardless if it is normal for my type of building and for Milan, but am curious none the less. Thanks folks.

Laura