I have a Bold 9700. This is the second time this has happened. It disappeared once before but is back. No unread messages. Any ideas

That's the style for that email service. I have it for my Windows Live account. And for Yahoo and email accounts hosted on Yahoo, I have the Yahoo logo. That is, until they disappear, like you are seeing. It is controlled by service book. You'll see that when they disappear, you can get them back by resending service books or doing a reset.

So do you think it just shows up randomly because other family members with the same phone and same service aren't seeint it?

It's the Hotmail icon. It's sent randomly by the carrier. Normal.

I don't know why it appears and disappears. You can experiment. Resend service books and have the others do the same. I know from experience you may have to resend service books a second or third time. But at any rate it is nothing to worry about. Whether the logo -- and it is just a logo -- is there or not makes no difference in function.