Why have my 13-month-old's sleeping and eating habits changed suddenly?
What you describe is typical of the second year. Your child is making so many cognitive, social, and language gains that things are usually on a roller coaster. Eating and sleeping, for instance, are less regular. Children this age tend to eat less than they did before as the rate of growth slows, and they sleep less too, often cutting back to one nap a day. Night wakenings continue, and if your daughter has learned to involve you in her sleep routines, she'll demand that attention during the night as well as at bedtime.
Keep her sleeping and eating schedule as steady as possible. Help her get herself to sleep at bedtime and back to sleep after night wakenings. If you are away from her all day, be sure you aren't unconsciously encouraging her wakefulness because you miss her during the day. And be sure that she isn't taking naps longer than two hours, as this will reduce nighttime sleep.