E.S.
My twin sons didn't want the sippy cups either. It is bad for their teeth if they take the bottle over a year. I was really worried about their teeth so I got a smoothie, sucked some up, put the straw in their mouth so they got the taste. THey learned really fast how to suck it up! So I got them off of bottles by transitioning to a cup with a straw. We couldn't get them to take sippy cups at all until my husband got the playtex soft tip ones. They are rubbery and almost like a bottle so once they learned to use them for a little I transitioned to the hard ones (my kids chew on everything so the soft tip ones didn't last long and are also choking hazards!). Good luck!