teething: do teeth always come in pairs?

my daughter got her first bottom tooth at 11 months old, and her second bottom one at 12 months.
at 13 months she got one of her top canine teeth, and now at 15 months she's getting her two front teeth at the top.
so she has one canine tooth all the way through and no sign of the other one at all, and getting more teeth in other places.
Is that something I should be concerned about, or is it normal?

It's not uncommon for just one to come through at a time. The other one'll come through when it's ready.

Most of DS's teeth came in two at a time but not all of them. They don't have to, though it seems like they do pretty often.

Quoting Rain (aka Mama):" It's not uncommon for just one to come through at a time. The other one'll come through when it's ready."

its not that they are coming at different times that concerns me, its the fact that her second canine hasn't come in, but other ones are starting to.
plus, canines usually aren't the 3rd tooth that they are supposed to get, so I don't understand why she got just one of them already.

DD had four come in at once, a few months later another four, two molars, two molars, two canines, and now one canine is coming in. It just depends.

DS has mostly had pairs when they come in but he had his first 2 bottom center teeth come in. Then one of the outside bottom center teeth came in. He had his 4 on top center come in and almost 4 months later he is getting his other outside bottom center tooth lol. It's totally normal.

My son seems to get 1 tooth at a time. As soon as one cuts through. It seems like a new one starts.