Sleeping pattern in children may be variable in different age group so if the baby is active and taking proper feeding with no other complaints most of the time there is nothing to worry. You have to just see the child should not be uncomfortable which may be because of factors like temperature of the room nasal blockage some discomfort like infantile colic or hunger. In older children a proper discipline is required so that the sleeping pattern can be scheduled according to a proper time try to avoid too much of screen time with sometimes can be the causative factor for disturbed sleep.

You haven't mentioned what are the other foods besides milk that you give . Generally a 1.3 years old child would not ask for milk repeatedly at night  if she has had a fulfilling dinner . So ensure that you have given her proper dinner comprising carbs and proteins e.g chapatti , Dal,  Sabzi or equivalent foods depending upon your dietary preferences . Just before sleeping she can be given a glass of milk . This should be sufficient to fill up her tummy for 5 to 6 hours and get sound sleep Also remember that as the child grows up her sleep requirements reduce . If the child is fresh with this much of sleep you don't need to worry . Children don't become insomniac like adults . Also if this disturbed sleep is of recent occurrence , besides hunger you should rule out any problem like blocked nose , fever , cough or pain abdomen or even discomfort at night ( feeling cold or too warm ) as the cause