Searching for caterpillars

Hi everyone, my nature loving 6 year old son is desperate to find some caterpillars. Unfortunately this year our milkweed hasn’t come up, and we haven’t been able to spot any caterpillars in our yard/garden so far and he’s been desperately searching every day for them. We live in Nepean, and was hoping someone could give me ideas on where we can look for some caterpillars and areas to explore. Thank you!