Per this website javelina's are normally in the 20-24 inch range in height and weigh 35-60 lbs. The one we killed and ate (outside of Eagle Pass, Texas) was close to the larger end of the scale.
I cannot imagine that you are talking about the javelinas as we have here...they are not anywhere near that big. They are not a foot tall. Sounds like you are talking about wild hogs. They can...and do..kill people. They are huge. Javelinas are tiny.
Maybe you're seeing a lot of juvenile javelinas, but I do know what a javelina is, and I do know the difference between them and a feral hog.
There's not much resemblance at all.
I saw both javelinas and wild hogs last Saturday evening and I had no trouble distinguishing them. The biggest javelina was actually much bigger than the little piggies I saw.