The leakproof CamelBak Eddy Kids water bottle 0.4 L (12-Oz) on Amazon (https://www.amazon.com/dp/B07HGSXM52?tag=quackdeals-20) is starting at just $8.90 on Amazon (there are many designs to choose and price can be varied). Free shipping with Prime or on orders over $35.
(https://m.media-amazon.com/images/W/MEDIAX_849526-T1/images/I/616Pq2vpEDL._AC_SL1500_.jpg)