What should I bring my host family in Costa Rica?

They live on a small farm. There is a mother who is 38, and we are considering bringing her an apron from Anthropologie, which are about 38 dollars, and very nice. The husband is a driver, and he is 45, I don't know what to bring him. There is an 18 year old boy, and again, I don't know what to bring him. There is a 12 year old girl, should i bring her something like nail polish, or slippers( cute girly ones)? And last, there is an 8 year old girl, and I am thinking to get her something similar to what I get the 12 year old. And last, I am thinking to get them a family gift of linens or towels. My mom lived in a foreign country, and was poor when she was young, so she thinks towels would be nice. It is most likely that the family is very poor, so I will NOT be bringing candy or coffee, or gift baskets, I would like to bring something nice and useful. Also, I'm a girl and 14, if it makes a difference. thank you
--------------------
Would the father like some high quality tools for his farm? A new toolbox or something along those lines? The 18 year old boy might enjoy a soccer ball, again, high quality so it won't break. I wouldn't get the 12 & 8 year olds nail polish slippers, instead I would bring the 12 year old maybe a kit or something with nice (not plastic) beads she can make into jewelry. The 8 year old girl might enjoy some stuffed animals or a doll with clothes, if that seems young enough to enjoy that. Or you could do something like give the 12 year old a book with the thread to make friendship bracelets and such (Klutz has one of these) and the 8 year old something with beads (again, Klutz) so that they have something to do thats advanced enough or whatever for them. Hope I helped have fun in costa rica! -D
Source