 Health and education are two of the main things we think about as being essential components of human capital. And so the interplay between generations of adult health and children's schooling has implications well beyond just the HIV AIDS pandemic because there's so many ways in which adults can be ill that can affect their children's schooling. And what we're looking at specifically is we're looking in Zambia, where the infection is actually worse than average. So in Zambia, 13% of adult, prime age adults, are HIV positive and 20% or one in five children lives in a household with an HIV positive adult. HIV infects one generation and affects the next. We looked at the expansion of antiretroviral therapy, which is the treatment for HIV AIDS in Zambia. So we're looking at the period between 2001 and 2007. In 2001, antiretroviral therapy was virtually unavailable in Zambia. Starting in 2004, there was a nationwide program to make antiretroviral therapy available to everyone who needed it. So from 2004 to 2007, you go from 0% of households have it to about 46% of households have antiretroviral therapy available to them. And this spread from 2004 to 2007 creates what economists call a natural experiment. And we're able to use this natural experiment to study the effect of adult antiretroviral therapy on children's schooling. What we do is more formally what we would call a triple difference specification. And what that means is we compare households who live in areas that never got antiretroviral therapy to those that had antiretroviral therapy by 2007. We look before antiretroviral therapy was available. We look after antiretroviral therapy was available. And then our third difference is we look at households where the household head is HIV positive. So if you think intuitively in the words of a treatment and a control group, our treatment group are individuals we see in 2007 close to an antiretroviral clinic who have an HIV positive household head. That's our treatment group. And everyone who satisfies one or two or none of those criteria, that's our control group. So you might be thinking, well, from 2001 to 2007, Zambia became much richer. And that's fine, right? It's all about the control group versus the treatment group. And the treatment group are those three characteristics, HIV positive household head close to a clinic that distributed antiretroviral therapy. And we see them in 2007. We look at three educational outcomes. Our children enrolled in school, our children age for grade. And the third thing we looked at is for just the seven year olds, did they start school on time? What we do find is really large effects on children being age for grade, meaning they progress a pace. They're not repeating grades. They're not being held back. They're not effectively failing a grade because of lack of achievement or lack of attendance. We also find really large effects in the seven year olds. So seven year old is the age of entry of primary school in Zambia. And we find that children are more likely to start school on time. And so we actually find no effect for school enrollment. And we think this maybe isn't that surprising because school was free in Zambia at this period. We want to know why this is happening. So we look at the illness in the household. So we hypothesized that children are more likely to go to school because they're not ill themselves or not caring for someone else who's ill in the household. But our effects are really large. So we think there's a lot more going on than just this illness story. And we think other things that are going on is improved mental health or mental outlook in the household. Children might have more mental capacity to focus on schoolwork because they're not worried about what's going on at home. There could be increased income in the household. There are probably many, many things going on. But unfortunately, our data just don't allow us to test all of these different things. There are two large takeaways from this work. The first is that when we think about the cost of a program and the cost effectiveness of a program or the cost benefit analysis, we often focus on who is directly treated. So in this case, that's the adults. But we found there's tremendous benefits to their children. So when we think about the cost benefit of a program, and this is an expensive program, we need to consider what's happening to other people in the household, other people in the community, and the interaction between human capital of multiple generations. The second implication is that we think about increasing children's schooling. We often focus at school. But this shows that there's a tremendous impact of the home environment on children's schooling. And we need to think more about the home environment in increasing children's school.