How on earth have you concluded that Happygran doesn't like her d.i.l. Summerlove? Would it be reasonable to conclude that her d.i.l. doesn't like her and that's why she still hasn't seen her 3 week old GC?
Of course not.
What GP's who live just a couple of miles away wouldn't be desperate to see their GC for the first time. The OP isn't just a visitor, she's the mother of baby's father; the baby's GM. Just like her d.i.l.'s mother and surely being a GM to this baby is just as important as being an aunt ie her d.i.l.'s sister.
What can be done about the avaricious and selfish
How Many Courses Do You Have in a Restaurant?

