Haha I mean it's a bad habit because now she reaches for all our cups. Including the ones containing coffee, juice, milk.. etc :P Things she most definitely can not have!!

What I've read about sippy cups is that they are only really bad if you are giving your child milk or juice etc in them and basically just letting the kid drink from the sippy cup for prolongued periods.

The introduction of the sippy cup has been correlated with an increase in the rate of many common childhood pathologies, including orthodontic issues, tooth decay, speech impediments and delays, chewing and swallowing problems, otitis media (ear infections) and even diarrhea. Note that many of the aforementioned problems are also linked to prolonged bottle use, and that the sippy cup is largely considered by medical professionals and child development experts to be merely another iteration of the bottle — but one that often ends up being used long past the age that is otherwise recommended for bottle weaning.

Regular and prolonged drinking from the hard spout of a sippy cup during critical periods of growth and development is thought to contribute to malformations of the soft palate, potentially leading to malocclusions (poorly positioned teeth/jaws), and a later need for expensive orthodontic work. Because bottles and sippy cups are mostly spill-proof, parents and caregivers are more liable to allow children to drink milk and juice over an extended period of time — even sometimes allowing these beverages to be taken to bed — which has been absolutely proven to increase the incidence of tooth decay when compared with consuming sugary (lactose and fructose) beverages in individual, time-limited sittings.

So if you only occasionally give the sippy cup, give water only, and don't allow the sippy cup or bottle to be taken to bed with baby, using a sippy cup is fine :) And once the child should be bottle weaned (around 12 months) if you're using a sippy cup that's when you should switch to a regular cup at the latest.

My LO can relatively easily drink from a regular cup if I hold it to her mouth, so it does seem like the sippy cup can be skipped :) We use ours as a 'toy' that she can have at dinner time when she sits up at the table with us, since we aren't giving her food yet. When she has solid foods and needs to drink more water, I'll offer it in a cup as well as the sippy cup, so that she learns both :)