Package Booking for 2 people at once

I have clients who are members of one family (mother and daughter) coming to my classes together. Is it possible for them to purchase a package of 6 weeks for the two of them at the same time? At the moment the booking system doesn’t give an option of bringing another person with you and multiplying the price by 2. Such option exists for a single class booking but not for the packages. Also, the current system doesn’t display the number of spaces still available in the class. So, these clients can’t see if there are spaces for both of them in the class.

I’d appreciate your help with this. 

Thanks for your reply. Unfortunately, this means I can't offer them a good practical way of booking, as they only come together. It seems I'll have to do it 'manually' for them to allow them to attend the class together. I hope your developers can improve the booking system fast, so I don't have to be too much involved with my clients' booking.
The previous version of Amelia's booking system displayed the number of available spaces clearly - why is this feature  not available in the current version? 
Thanks. 

Hi,

Previously on the booking page of my web site, the number of available spaces for each class was visible for everyone. I think this was the case when I used the Standard Amelia not the Pro One and I used 'Events' for scheduling my classes. Now I use Pro version and 'Services' to schedule my classes (and include an option of packages). In this way, the booking system  doesn't  display the number of spaces to customers.  I can only see this info in my calendar when I'm logged in and have my 'internal' view of my site. So my clients or potential clients don't know how many places are available in each class. When the class is full the system would not allow them to book themselves but that's the only way for them to know.    

So I get emails from potential clients who want to come as a group of two or three friends asking me how many places are available in the class. The system seems not very efficient at the moment and it makes me wonder if I should change to a different booking system. I only run a few classes so I am still closely involved with my clients but if I grow bigger I can't afford to book in people manually and constantly answer emails about the numbers of places available.  This all should be automatic. 

See attachment that shows a view from the client booking system. The Calendar dates in some cases are partly shaded in. One would think that this is an indication of how full the class is but it doesn't quite tally with the bookings. What does the shading on individual dates represent?

Many thanks for your help.