Child is preferring me over mom for everything. Help!

I have been with my current little charge since she was 4 months old. She just turned 2 last month. In the last couple months she has become very bonded to me and literally wants me for everything. If it was just her and I throughout the day, I wouldn’t think twice about it, but Mom works from home most of the time when she doesn’t have appearances. So, she does like to be involved in parts of LC’s day which is completely understandable (helping put her down for nap, come downstairs to see her occasionally, etc).

However it’s gotten to a point where I cringe inside every time LC screams for me or runs to me and physically pushes mom away. She throws a fit when mom goes to change her diaper and yells for me instead. When nap time comes she has melt downs and tells mom she wants me to sing her to sleep. It’s getting so bad that I’m seriously fearing losing my job!

I feel awful for mom because I know her, and I know she dies a little on the inside every time LC does this (and so do I because it would break my heart if I were a mother too) She just won’t show it. She is currently pregnant with baby number 2, so maybe that has somehow influenced LC’s new behavior? I have heard a lot of toddlers will begin to bond a little more with others in the household (dad or nanny) when mom is pregnant but I still don’t know if I believe that. Anyway, what can I do or say to quell this behavior?

Also, it’s worth noting that mom is a wonderful, loving hands-on mother who spends plenty of time with LC so the “maybe you spend more time with her argument wouldn’t apply to this situation.