Two problems can appear:
nighttime waking and development of negative associations with sleep (as when your baby gets used to depend on rocking or
feeding, as a prerequisite to sleeping)-- this is
usual as for newborns so for older children.
Try to set a bed time, then have a bed time routine: a longer than
usual feed to keep baby satisfied for longer, changing into a fresh diaper getting into
nighttime clothing (an all - in - one or romper is a good idea for the night), some quiet time, perhaps a lullaby or a reading / telling a story.