It's a confusing issue, because many of us shampoo our own hair daily and consider this the norm. In reality, there's no need to shampoo every day. What's more, daily shampooing can dry out the hair and scalp. Unless there's a medical reason to shampoo more often, weekly or even less is fine.

Shampoo your dad's hair when it looks, smells, or just seems dirty, or if he's scratching his scalp and appears uncomfortable. Shampooing less often may leave his hair looking oily after a couple of days, but this doesn't mean it's dirty. These natural oils are actually good for the scalp and hair. However, if your dad wants frequent shampoos and this makes him feel good, no problem. It's always a good idea to maintain his preferences. If he doesn't seem to care, then you can make a judgment call.

Combing his hair daily is a good idea, though. It will keep him looking neat, circulate the natural oils, and allow you to keep an eye on his hair's cleanliness.