Release Forms

I wasn't sure where to ask this question so thought this was a good start.

I sent an attorney friend of mine my smugmug website to view some pictures. I'm not a pro but shoot some family events and put them on the site for those I shot for. He asked if a release or consent form is necessary for me to post these pictures for viewing? Can someone advise me on what the guidelines are in regards to this? Also, how does this pertain for instance with street photography and posting in the same manner?

Are consent/release forms only pertinent when a profit is made?

Thank you