Lace bonnet with cotton lining.
Little girl in the photo is wearing a 2-3T she is 3 years old.
Bebe Theory size chart measurements in inches:
Bonnets (circumference of baby's head):
0-3 months- 11.5
3-6 months- 12
6-12 months-13.5
12-18 months- 14
18-24 months- 14.5
2T-3T- 15