There's a measles outbreak in our area & DS2 hasn't had his booster yet. I rang the surgery & they said he can have it from from next month - the limit is from 3yrs 4mths. I'm just uncertain because he'll be right at that limit; DS1 was 4 when he had his. Neither of them has ever had any bad reaction to vaccinations, & I really don't want DS2 to get measles!