Please give details of the trains you'd like to book. Date, departure time and route for each train.

The best way to book depends on the train, so that's why details are important.

Hi, most reservations will not be open yet now.

From Lille I would suggest to travel with Belgian IC trains (reservation not needed) to Brussel and from there German ICE trains to Cologne and change there to ICE to Hamburg.

You can also travel via Antwerp and The Netherlands to Hamburg. Reservation not needed, except optional in IC Amsterdam-Berlin and ICE. I would suggest to not use Thalys (reservations are very expensive).

From Hamburg IC trains to Copenhagen and Öresundbridge trains to Malmö and SJ Highspeed train to Stockholm or Nighttrain directly Hamburg-Stockholm.

For German Trains (ICE, IC Amsterdam-Berlin, IC and EC in Germany) you can reserve via Deutsche Bahn a Family Reservation, but it is optional. For trains to Copenhagen reservations are not open yet.

Thank you very much for your replies.

The night trains between Germany and Sweden can be booked until the end of September. However,  not all departures are open for reservations yet due to uncertainty about track works. 

We were able to reserve some of the trains.  The one leg of the journey that is still giving us some difficulty is from Hamburg to Copenhagen on July 27th.  Approximate departure time 10h, any route would be fine.  

Thanks in advance for your advice!  

You'll be able to book it here when booking opens : https://travel.b-europe.com/dsb-rail/en/reservation-only#TravelWish

Looks like seat reservations become available 3 months in advance