There are a few instances where a baby raccoon could get separated from its mother. When relocating her babies, a mother raccoon may place her babies in a known safe location to await her return while she either scopes out where she is going next or while she relocates one of her other babies.
It is not uncommon for a baby to get separated from its mother during their foraging. While the human urge is to want to help the baby, in reality that action can actually do more harm than good. In most cases the mother raccoon will return to collect the baby provided there is no human interference.
Raccoons are amazing mothers and will come back for their babies. It is common for a mother raccoon to return for her young at dusk or during the dark of night so don’t be alarmed if the baby is still there a few hours later if it is during the day.