This person seems to have a rather common wealthier family member or upper middle class attitude to money, which is understandably alienating to some people with less (even if it only works on ones who were already sensitive or taking it Very Seriously, it becomes a sore point only because the rich relative is pushy and insensitive about it). They're being pretty unfair to their friend by squishing her between their pressure and her spouse's feelings, but the question at hand is more... what kind of magic suggestion do they think an advice columnist would have that would suddenly make the kid's dad change his entire outlook on life or whatever? There are no magic words, lady. This isn't a Jeeves and Wooster story. If the kid's 18, they're free to accept monetary gifts or not on their own behalf, but you're not getting away with something like this without creating conflict between either you and the dad or the kid and the dad, or both.