It almost seems as if he did not dare to take up his position as Crown Prince before his fatherhood. That he just felt he was entitled to it after it was sure that he would keep the line going. They clearly suffered a lot by their childless time and it makes one really happy to see how happy they are now.
You may have a point here. In this context I can only applaud to Felix and Claire for staying out of Lux as much as possible, they never ever gave the impression of wanting to outshine Gui and Steph.
Right now, it certainly contributes to the HGD couple's happiness and wellbeing that Henri and MT have already left for Cabasson
(this "hard working" couple needs 3 months of holidays), so Gui and Steph have Lux to themselves so to speak. I guess the young family will spend the summer at their beautiful home Fischbach, which due to its moderate climate is much healthier for both, the baby and the mother still recovering from the c-section.
I thought there will still travel restrictions in place - but of course they would not apply to MT
I presume she manages to overcome her distaste for flying as it would be a long drive or train journey