Baby Sleep Issues - 0-3 Months

I discuss the sleep issues we've had since Zaden was born and the book we've found very helpful, "The 90 Minute Baby Sleep Plan". We're going through a very tough time right now with him being fussy all the time, which I think is due to lack of sleep. I thought it was teething for awhile but the more I read about the signs of too little sleep, the more I'm sure he just needs more. Any help or advice would be great. We're thinking of trying The 3 Day Sleep Solution by

Starting Baby on Solids