The more complex life is the rarer it's going to be.
Nevertheless, with a big enough stage it's going to happen somewhere - and even that part of the universe of which we can conceive mathematically is vast beyond human comprehension. So I'd put good money on it. The idea that there's no life (intelligent or otherwise) anywhere else but on Earth is really quite laughably parochial, more suited to the tiny hole-and-corner universe of theism than science. An incredibly rare chance event, given a large enough stage and sufficient time, will occur repeatedly, thus making it not that rare over all.