A 19 month old, by most psychologists, is still considered to be in the "baby" stage when it comes to learning and growth. Keep in mind that 18 months is exactly a year and a half old; this is one of the "milestone" ages that many pediatricians request a wellness check. A 19 month old could be considered under the same framework as an 18 month old baby. Though it may vary from one doctor or psychologist to another, there are really two general areas which are monitored for learning and growth development in all children.
The first area is physical and motor skill development. This area answers "What can my baby physically do?" Most 19 month olds are fully walking, and beginning to run (though this movement may be stiff and they may fall frequently), climbing, and going up and down stairs correctly (though possibly with assistance). Fine motor skills include the grasping of things in the hands and fingers, therefore, most 19 month olds can feed themselves with a spoon, drink from a sippy cup, scribble with a crayon, and turn thick pages of books or several thin pages at a time.
The next area is sensory and cognitive development. This area answers "What can my baby understand?" Typical 19 month olds can show affection (give hugs and kisses, and snuggle for comfort) and may or may not have separation anxiety from mom and/or dad. Cognitively, this is still very much an "imitation" stage, however, most 19 month olds have a vocabulary of at least spoken 10 words, and can point to several specific objects when named and identify several body parts. This is also the stage where the "my" phase most often begins, as this age is the beginning of self-awareness and ownership.