my kids call my sister Nanay simply because she took care of them most of the time, and that is OK. they know who i am and who she is. I am their mom/mommy. It's just an endearment naman, wag magpakastress. what matters is how u build the relationship with ur child and get them to understand who's around them. but that depends on your relationship with your SIL. if it makes u uncomfortable, then politely tell them. they also call their lola as Mama simply because yun ang naririnig nila from us. depends on how ur environment is like. goodluck
Anonymous