We started the other two at 4 months old. My son started that early because he was a little chubby piggy who wanted to eat all the time. We spoke with our pediatrician who told us that single grain cereal was fine for his age, and he loved it. I did the same thing when our first daughter was born, because that is what I had already done. This time around I had heard that introducing solids before the child's digestive system was finished developing could be harmful. Now we had the problem of when was that, some said 4 months some said 6 months, so we tried to research more, but all children are different. We talked, researched, and prayed.
Finally, we had an answer and it was so simple. For about the past 70-80 years, modern medicine and technology has come a long way, and in that time "folk remedies" and "old-wives tales" were considered ignorant. Up until the past couple of years these things were something "Grandma would say she used to do" people would just roll their eyes. Recently scientists are starting to realize maybe Grandma wasn't as crazy as they once thought. They are realizing that pesticides are not as great as once thought, that antibiotics and vaccines are not as great as once believed (necessary sometimes yes, but not as life or death as once was believed-FYI I am not starting a vaccine debate), and even the once thought necessary interventions during childbirth, I could go on, but that is not the focus. We would wait for her to get her first tooth. We feel that would be her body's way of letting the outside world know that she is ready for food.
Really we could have started with a plethora of things, because she was technically "old enough" (according to medical charts) to have many fruits, vegetables, and grains. My son ate whatever the baby food jars said he could have, you know according to the little pictures on them, "sitter", "crawler", "toddler". When baby #2 was born I did the same thing until she was about 6 months old when I got sick of it and started just mashing up whatever veggie we were eating for her. I did keep a jar or two of baby food for pizza night. Her first official food was carrots, she is still unsure. I started by making a batch of carrots and frozen them in an ice cube tray, but I gave that up quickly. She has been grabbing food from her siblings to try to eat for about a month.
We are currently cutting food into chunks she can mash with her jaws, and that are small enough not to choke her if swallowed whole. She is old enough to feed herself and does well with it. She enjoys banana, carrots, rice, quinoa, and just today we tried "Puffs" ( Gerber snacks). I was a little nervous about choking so I broke it in half. She did well even with a whole one that her brother so sweetly gave her trying to "help".
It is nice not having to worry about bringing food for her if we are out or worrying about what we are going to feed her if we are out too long. She is her happy self eating her food!