No it doesn't. It means the two households can act as one household, it's not just for childcare.Still doesn’t mean she can have lunch with his sister and her husband, that only covers the child.
Seems like the household is that way out which is probably why Kirsty is so welcomed there.Deffo not under 1 the sister is a twit also she should be taking more care when pregnant not hanging out with the pair of super spreaders