My older son (not baby led weaned) started on the 25th, went up to the 75th and settled on the 50th. So I don't think a bit of meandering around the centiles is a problem at all. I have had more of a problem with my second, as since about 5 months, he has been slowly drifting down the centiles (from just below 25th to just above 0.4). I worried that this might be because he has been very slow at learning to eat, but the paediatrician didn't seem to think this was a problem. He was more concerned that the lack of eating and the low weight gain might stem from an underlying illness. Hence we are currently having tests for coeliacs and some other stuff. Personally I think it is just his genes, as my mam said that I didn't gain weight easily (and some other family members were the same too), and she says Euan looks just like I did weight/sizewise. Anyhow, his eating has picked up a little recently and at his last weighing, he was starting to move up more towards the 2nd centile.