The only way to find out if the vanilla gene is present is by breeding it to a fire, (fire x vanilla combo is vanilla creme which is very unique) but I truly don't think it's vanilla. That isn't to say you don't have something going on there though. It could still be something, or it just be that the mother is a nice light normal that passes that light trait on to the babies and lightens them up a little..
Kind of like how breeding a dark normal to a pastel will most likely give you dark, low quality pastels. Breeding a light normal that has nice blushing to a pastel will often improve on the pastel traits, giving you much nicer pastels that are lighter and have lots of blushing.
Selective breeding is how you produce nice morphs. Maybe you have one of those nice normal females that will improve everything you put to her.