Avatars not showing in text message app.

I know it's been almost 2 years since you posted this question, not sure if you still have your mytouch4g but it may help other users.

I noticed that the avatar pics disappeared when I matched the sim number with the phone. and that people I added to the phone and not sim have the pics show up. Bottom line, to make the avatars show up, either delete the sim numbers or erase the area codes from the numbers saved on the sim.