I did as much reading about this in every book, website, blog, etc. that I could for a while and I kept running into contradictions (which were probably just somewhat educated opinions, now that I look back on it). So I developed my own educated opinion! My dd is 15 mos and still mostly survives on breastmilk. She does eat solid foods--well, she PLAYS with solid foods and puts them in her mouth and spits them back out again mostly--but the crux of her diet is definitely bm. She drinks a lot of water over the course of the day, so I know she isn't dehydrated--mama's just got the goods! She's in the 99% for weight and you can't argue with fat and happy. I say trust your gut. If the kid is growing and thriving and the two of you are happy with the arrangement, let her tell you what she needs. I watch out for signs of vitamin deficiencies and especially iron (cracking fingernails and listlessness is a big one), but I firmly believe, most of all, that every kid is different. Period.