My son who is 2 months shy to 4yrs have never slept through out night since birth. He wakes up almost an hour or 2 after sleeping and then every 30 minutes whole night. These days he ends up sleeping from morning 5 to 7am continuous that's the max I have seen. Every time he wakes up he cries  screams yells fights and bangs his legs in sleep. His sleeping habits are not just effecting him but also my health due to less sleep.