I have several helmets. A couple that fit my big melon and 4 that are more appropriately sized to riders.

My mom was a big supporter of my riding. She had one rule the first day and it carried on until she died. "Always wear a helmet". I bought a Ducati (RED) a few years before she died and I took it to her place to show it off. Arizona doesn't require a helmet, it was only a few residential blocks so I rode there bare headed. She wouldn't even come outside to look until I went home and got a helmet. It's a good rule :)