Personally, I wouldn't make your girls go. They'll just get more upset, by the sounds of things. We have a similar thing with my in-laws: they're a lot nicer than yours, just they do favour BiL more and I'm a bit nervy about what they'll be like when DH and I have children (I'm fairly sure PiL won't want any favourite other than niece, but you never know...). I'm not "allowed" to say anything to my in-laws either, though it bothers me that DH has to "pay them back" for birthday presents with work on their computer/house and don't want my children to go through the same.

My own mum was ignored by her grandma and was made to visit and hated the woman - she died when I was 7 and I never met her. In fact, my grandma used to frequently have it out with this woman (her mother) about loving my uncle and ignoring my mum, even at my mum's first birthday (there's 1 year 2 weeks between her and her older brother), mum's nan brought her brother a shedload of toys and my mum nothing - my grandma returned all my uncle's gifts to her mum and chowed her out.

Anyway, just to say my mum was forced to see her nan when she was younger and once she was old enough not to, she never saw her again or went to her funeral. So if you force your children to see them now, they may not want to if their grandparents decide to change later on.

Sending you lots of cyber hugs, Dinky - I really think this is going to be a tough Father's Day and creating more problems with people you love is not the best of things, even if you're only doing it to avoid problems with people you never really see.