Hello, I need opinions please! DH wants to t...

Hello, I need opinions please! DH wants to try 10.5 month old DS on cow's milk but I am against it until he is over 12 months. The reason he wants to is because we are having a hard time at the moment getting DS to drink his formula and he thinks that DS may drink the cow's milk as it is something 'different'. DS is teething at the moment and also has a throat infection (he is on antibiotics)which is why we are having trouble. DS is drinking well over 200mls of water each day and is eating his meals which is why I'm inclined to ride this out hoping that all will return to normal as soon as he is feeling better. My mum's suggestion was to put chocolate flavouring in his formula, needless to say I am ignoring that advice. Am I right in waiting?