L.N.
i never bit my biter babe. i don't know how to explain to such a young child that it's ok for mami to bite you but not ok for you to bite your sister.
she would bite constantly ever since she started getting teeth. she'd get time out if she bit her sister.
around the 2 year old birthday she got tired of timeouts due to biting and she stopped biting.
good luck
vlora