Did you hear the woman on Woman's Hour talking about having relationships with your adult children. She said that most Mothers said they had a good relationship with their Son in Laws but when they dug deeper they found that they hardly ever saw them or spent time with them. On the other hand they would always complain of not having a good relationship with DIL as they seemed to expect a lot more from them, to spend time with them, for them to be more 'daughterly.'
I always suspected this double standard was a thing but it's interesting to hear that this study backs it up. I know my MIL at first expected a close relationship with me; wanted to go shopping together etc. My own Mother however barely sees or bothers with any of her SIL and couldn't give a shit. My Mother has had it easy I suppose cos she only had daughters so never had to tiptoe around DILs with new babies etc.