In-Laws Relationship

Been trying to make arrangement and adjustment just so MM and DD can go KB visit KC's family but I guess DD and MM has their reasons - though finally MM proposed to go on the 1st and return on the 2nd.. erm, with us on the 2nd morning flight? Well, I don't know what else to think, she is usually a very practical person and I called her to talk voice to voice, however I guess she is also not very interested, if possible no need to go, next time she says. Well, you know how its like when one says 'next time' probably never huh? Furthermore they know I will be going back overseas, how often can we have this chance? But I'll just stay positive, I know they don't like to be forced and I dont like to force either but I must say, my heart very disheartened coz I also already expressed to them I really would like them to visit KB and family esp Mom who have not met them... But, as with GNNY's case, if no will and no interest, there will always be barriers, this and that .. so, just gota stay positive and move on with life .. :) Recently, before this, I was also observing what's happening between them and WG/LS, though it would be nice if WG would contact them more, visit them more, show more of his love for them, but I figured you know you can't just blame one party.. it really takes two to clap, and if the younger generation doesnt know how, why can't we show them? Why can't we set a good example.. it came to my thoughts that, I don't think they even take the time to wish their DIL and SIL Happy Birthday.. and yet I always though it would be nice if we all rememebred their birthday, but how can we expect them to do all these when the elderly ignores it the other way around..? Of course we could but you know, things don't always happen that way .. so the others should not be so 'siu hei' and should initiative good actions.. However, MM and DD will always remember me and WG's birthday.. so you know, they kinda just focus on us, have they really accepted their SIL and DIL?