Or perhaps she is a wise grandmother that is well aware of exactly what an utter twit the boy can be.
It is distinctly possible that there is well founded concern that he can’t be trusted with chopsticks much less a baby and a gun.
Who does it benefit to assume malicious interference without clear knowledge of why she did it?
Well, you have a point. But I have known of a LOT more interfering moms than I have wise, discerning ones I’m afraid.