Css column-count should respect only first child

I'm trying to use the column-count to make a kind of week calendar to user tasks.

The main div of the week has the property of column-count to 7 and ALWAYS there will 7 childs. The seven days of this week.Inside this days there are the tasks, but the number of tasks is variable and it break the column-count logic.

Why column-count not consider just the first childs inside it?

Here's an example of what I'm saying: https://jsfiddle.net/nby5ctb2/

On the second list, I wanted the tasks 1, 1.1 and 1.2 on top of each other, and when there are no childs just skip these day.

The css I used was just this:

.week {    -moz-column-count: 7;    -webkit-column-count: 7;    column-count: 7;}

Thanks advanced