the bwv used to have them - there were called dedicated pluses.
not all dedicated studio were pluses. MS no longer allows members to request this. these are not guarantees and won't ever be.
that say these rooms are tiny - you will be very uncomfortable.
the day bed was really just a luggage place - it was much to hard and small to sleep on - your 6 year old would be the only one.
go for a 1-bedroom AKV standard - it is definitely more - but you can sleep 5 here comfortable.
when the new BLT opens up you can also stay here in a 1-bedroom.