Ottobre. I just looked and issue 1/2007 has a lap tee and lap tee dress pattern that goes up to 98 cm (which is between 3 and 4 I think). I made the dress in a size 62 and an 80 (I think) and it runs VERY wide so you'd probably be fine using it for a 4 year old. I would just measure a shirt that fits against the pattern sheet first.
You can get Ottobre back issues at sewzannesfabrics.com.

vicki