10mo old waking every hour

[Palooka]

For both naps and bedtime he is waking every hour on the dot, our sitter jokes she could set her watch by him. Sometimes he cries for 5 minutes and falls back to sleep, but most of the time we have to restart the whole routine or bring him to bed with us, where he again cries every hour until morning. This just started and it's already old.

any ideas?