Love / A suitable birthday gift for a Polish lady? [26]

i have a female friend in wroclaw. as she told me, her birthday (or namesday?) is in next month. i would like to post her some gift.

she is between 28-31, married, has a child.

just as someone mentioned in the previous thread about expensive gift, i have no idea what is suitable. a painting, toys, chocolate?
and what do you write in the card? just happy birthday?

what is the average income for a high school teacher in wroclaw?

thanks so much.