My daughter is two years old—when must she wear the hijab?

The hijab is obligatory for an adult Muslim woman, based on Allah's saying, "And let them draw their headcovers over their bosoms." As for a young girl, she is not obligated to wear it, but if she reaches an age where men's souls become attached to her, her guardian must compel her to wear the hijab to avert fitnah (temptation/strife).

It is not forbidden to look at a young girl who is not suitable for marriage, nor to touch her without lust. Her awrah (private parts that must be covered) does not need to be covered before the age of seven. The awrah of a girl between seven and ten years old is like the awrah of a slave woman (what is between the navel and the knee). However, between the age of ten and puberty, some jurists consider her like an adult woman, while others consider her like a slave woman. The guardian should raise the young girl to observe modesty and virtue, and accustom her to the hijab when she reaches the age of desire.