Yes I definitely agree grandaprents should love all their grand kids the same.

One perspective might be that older generations might feel the "main" parent or caregiver is the parent, which even today timewise it the general thing, for sahm's and often mums can be more strict or set on routines, ways of doing things etc (just as a generalisation) because with sahm's (well at least in my situation...dh is VERY invloved father and equal to me as a parent...but) I set a lot of the routines, what food when, how much, sleep tomes etc...just as a practical thing because i'm a sahm so i am the one dealing with the kids day after day and structuring their days. And so (not saying this a reflection of you actions or personality) but perhaps mil feels shecan do more with you neices and/or nephews as their mum is her dd????

Also its possible ur MIL is just a dip stick??? haha

With our familys our 2 ds's are the first and only grandkids on either side so far and dh's parents moved back to nz after 20yrs here when i was preg with ds1 so mu mum is much closer to the kids for obvious reasons but dh's parents will be moving back in the next while so we will see what happens then