Its not really necessary. Sippy cups was invented to make weaning off bottle easier and start drinking normally with a cup or straw. If your child refuses you can try some other steps to get him to get use to sippy cups. Examples:
Dip the spout into breast milk or formula before giving it to your baby. ...
Switch halfway through a feeding. ...
Modify the sippy spout. ...
Work in reverse order. ...
Offer your baby a straw. ...
Try other beverages. ...
Show your baby how it's done.
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