I am now an awful DIL, before children I was very, very good.
DH was the middle golden boy but behind him was me saying phone your mum, I've wrapped a present, etc. DH went on large family road trips to Australia, Morocco, etc in the first 5 years whilst I stayed behind working/saving because I did n't have the same cushion of wealth. 20 years later we're still together.
MIL has always been very direct with me that once one her children has split up with a partner she does not want to hear from them. That was repeated with every failed love affair of her other children. I guess that was fine when we were all in our 20's with no DCs but I've been apart of that family for nearly 20 years now.
As soon as DH had had one roast dinner at my mums he was part of the family and my parents joked that they would stay in touch with him rather then me. That's a much warmer emphasis to build a foundation on.
Once we'd delivered the first couple of grand children and had the first ever minor falling out I realised I don't have to be bothered, I will always be the outsider. Being a grand parent is a learning curve but my children are not there, as they repeatedly suggested, for them to 'practice' being grand parents so they can get it right with the ones that follow.
If you lay your foundations warmly with an open heart, you might be upset when relationships fall apart early on but time goes pretty quick.
Met MIL when I was 20, I got married at 26, had DCs at 32 & 34, stopped making an effort when 35, now 39. I'm polite about them but not 'warm'. I don't ring them, send cards, invite them to my house that's up to DH and most of the time he does n't bother.