I am a bit confused as to how often you visit, you have said that you are expected to leave from dog sitting as soon as they return but also say that you only see your grandchild for a few hours, Are these extra visits not related to the dog sitting?
The baby is only four months old so surely the French trips have not happened very often especially as you say they are planned weeks in advance.
The French visits are not just about the baby, your daughter-in-law probably wants to visit her family regardless of the baby.
Some think twice-yearly visits are acceptable, and some weekly, you need to ask what the parents think is acceptable and accept it even if it is not what you want to happen.
Trump has only been in office 4 days
A quote for those blessed with a spouse:


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