It's not a space family, it's actually blended (I had one with Majorite as the other parent). You would have to mate two planetchi, which you can't as far as I know. I don't think Sunnytchi appears on two consecutive generations, and you can't connect mate them as you only have 1 egg. People always call it a space family, which doesn't actually appear to exist.
According to GK1 on Tama-Zone's chart, you can't get one. Just search on Tama-Zone. If you did get one, post a pic. Otherwise, space families are a popular myth.
You have one space baby and one space parent. You also have one non-space parent. To get a pure family, all members have to be from the same group. As I said before, you can't get two space parents, unless you debug. And interestingly, even when you debug, two space parents and Iwatchi babies result in a blended family. Someone on Tama-Zone tried it, can't remember who, so I know it's true. Impossible to have a family with all space characters naturally, so there is no space family. Check a V5 growth and character chart, trust me.
Here's a link to a growth chart (scroll down to part 2):
You have to get one hudred percent um... -Thinks- Something about getting one hudred percent with the family before and then you can get the Space Family