We are meeting friends this week-end who said they have deliberately let their 5 month old mix with a toddler with chicken pox because they believed it was better to catch it early and it was milder in babies. They said although he has no spots he has had a mild fever and been more sicky. My baby is also 5 months. Should I be worried about her mixing with him? Would it be 'better' if she had it while very young?