usage of when and tense in a conditional sentence?

There are two conditional sentences which one is more correct grammatically?

1. When I come home, my children will be playing.
2. When I come home, my children would be playing.

In the first sentence the when clause verb is in simple present, and the main clause in future continuous. the situation is real that the children will be playing when I reach home.

In the second sentence the when clause verb is in simple present but the main clause verb in past continuous. But how the second sentence also sounds correct?