Anyone?

My 7 month old is extra clingy. She only wants mommy every sec. won't go with anyone for more than 3 seconds. Is this normal (yes I hv heard of separation anxiety around 6 months to 24 months. But this much?) I mean, ever since she was born she has been seeing her grand parents (my parents) who live with me. And it now was happy in grandpa's arms but now naaah! How did mommy suddenly be her fav?