Chaotic FaceTime sessions !

When GDs are with me I will put Skype on so they can talk to their Aunt but they usually just say HI, wave and wander off. The eldest GD can sit for an hour playing a computer game but can't hold a real time conversation on the same computer.
I understand it is difficult to get to talk to DD, I have only spoken to mine once in the three months since she was in the UK.

I find Facetime/Skype is never what you expect it to be! I have it the other way round - lots of chat with DD but very little with the gc who shout and scream, make faces, stick out their tongues and become extremely over-excited and decide that now is the moment to want something from their Mum . Nina's suggestion is a good one and I am sure your DD will want to have a long chat with you in more peaceful surroundings.. 7 is still quite young to sit still in front of a screen for any length of time and hold a conversation with Granny - my 7 year old is usually baring his backside at the screen or making stupid faces . Good luck.

Oh dear, I can understand your frustration. DGS regularly reads to other grand parents in Germany via facetime. DD sets him up with the book prior to making the connection. Could you ask DD to make sure your DGD has everything to hand that she wants to show nannie. You say you've asked DD to call after bedtime which is a good idea. If it's not happening maybe ask when it would be convenient to call her. Explain that it's lovely to talk to DGD but you'd love a chat with her too.