My cat leon is missing and he is only 2 years old, he is my most favorite cat, and i am so heart broken....

I dont know what to do, I live so close to the highway and to main street, I haven't seen him injured or deceased anywhere on the road THANK the LORD ABOVE, but I dont know what else to do...I live in a fairly small town, and have been up and down all the closest streets next to me...he has been gone b4 for about 3 days, but came back, but this time he has been gone for almost a week!!! He is such a unique beautiful orange tom cat(he is fixed), with such a wonderful personality, my mother's cat Josie went missing about 4 months ago(and she is still so heart broken over her, and now Leon), and we never found her, but my mom thinks she ran off because of the people who cam e to mow the lawn and it was her first couple of days of being outside, but Leon has been an outside cat for over a year...but its so strange how two cats have just vanished like that..it worries me so much, im sooooo sad...

I didnt think he would go too far because he is fixed, but I guess that doesnt matter...