Originally Posted by Catherder:
Most likely child is feeding off Mom. 
If mom dreads drop off because of her child's previous reaction during the typical 8-10 month old "stranger danger" phase and continues to act nervous, so will her child. (Mothers guilt is deadly 
)
If mom acts nonchalant, so will child.
I tell my moms this when their child is a newborn, I remind them often that I "predicted it" since I am a wizard. 
It is a running joke and I offer them my "magic ball" (what to expect; The toddler years) from time to time.
We laugh alot here, it makes it easier to not feel judged, but part of the joke, YKWIM? 
Beg mom to test the theory with a big smile, double dog dare her if it will work with her personality....make it something fun between you and mom.
Send text photos of child playing just minutes after Moms departure to alleviate Mom's fears often if possible.
Typically, IME, she will laugh or hug your neck when she see's how quick it stops. 
I agree. My worst experience was a kid whos own mom cried when she dropped off. After 8 months we "agreed"
it wasn't working out. Moms mental health issues were rubbing off on the kid and she always had a terrible time at daycare.
I also agree with the poster who said other things can be affecting it. I expect some kids to cry some of the time at drop off. If it lasts for a really long time everyday then I would be concerned. I figure it comes with the job.
My kids all wave to mom/dad in the living room window when they leave and this helps. I also do a reading time where all the kids read at drop off (all get dropped within 20-30 min of eachother). All the kids read with me until breakfast. I sit with the ones who are having an especially rough time at drop off and read books to the whole group. Once they see the rest of the group having fun and enjoying themselves the crying tends to stop.