A bottle assembly includes a container having an open end, a closed end, a base portion, and a neck together defining a liquid chamber within the container. The neck has a rim defining the open end of the container. The bottle assembly also includes a collar assembly generally defining a closure for the container. The collar assembly is configured for releasable engagement with the neck of the container over the open end thereof. The collar assembly includes a collar and a nipple. The bottle assembly further includes a cap including a closed end, an open end, and a side wall extending between the closed end and the open end together defining an interior. The cap is configured for releasable engagement with the collar assembly such that the nipple is received within the interior of the cap. In some embodiments, the bottle assembly includes a vent assembly positionable at least in part on the rim of the container to permit venting of the container during use.
