Randomly select from a subgroup of household members and apply repeat

What is the problem? Please be detailed.
I have created a section to collect information for a roster of all household members. Next I have a section on child labor, in which I would like to first randomly select two household members/children who are between 6 and 16 years old and then use a repeat group to ask a set of questions for each of the 2 randomly selected children.

Is it possible to do this using XLSForm?

I believe that first I would have have to verify if in the household roster there are any members between 6 and 16 years. If there are 0 members in this age range, then I would skip the whole section on child labor. If there are 1-2 members, then I would ask the the question in the child labor section for these 1-2 children. And if there are more than 2 members, then I would first randomly select 2 and then ask the questions.

Any help on how I can do this in XLSForm is much appreciated!!