Hi A.,
I HIGHLY recommend reading "Healthy Sleep Habits, Happy Child" by Dr. Marc Weissbluth to understand biological sleep rhythms. You didn't say what his sleep schedule is like but this was my daughter's at that age. Wake up at 6:30-7am, morning nap at 9am, afternoon nap at 1pm and bedtime at 6-6:30pm. I adjusted times a little depending on how well she slept during her naps and her overall appearance. Per Dr. Weissbluth, the BIGGEST reason for nightwaking and difficulty falling asleep is too late a bedtime. It sounds as though he is really overtired. "Sleep begets sleep" as Dr. Weissbluth says and I found it to be SO true! If my daughter (almost 3 yrs old) goes to bed too late, she ALWAYS wakes up at night and wakes really early in the morning. She has stopped napping and is asleep by 7pm at the latest and sleeps until 6:15-7am. I believe ALL babies can become good sleepers if the parents are willing to adjust their lives/schedules to accommodate the child's need for sleep. (So does Dr. Weissbluth)
As to the rice cereal, my daughter could never tolerate it so I gave her oatmeal instead. The rice just gave her a tummyache and difficulty pooping.
You and your hubby need to be well rested in order to be good spouses and parents. I REALLY understand what being exhausted does to a marriage, I pretty much cried ALL the time and thought I hated my hubby as I was the only one who got up with our daughter. Things are terrific now so there is hope for you! :)
Email me if you want more info on Dr. Weissbluth's methods. Always happy to help and share.
Sincerely,
L.